WELCOME to what started life as "Doc Brown's Chemistry Clinic" in 2000

but now extended to some biology and physics !! All © Dr Phil Brown 2000+

Short version of my homepage with the main links on (SITEMAP htm file)

Short version of my homepage with the main links on (SITEMAP pdf file)

email doc brown There is also Doc Brown's Travel Pictures to explore!

WEBSITE HOMEPAGE - INDEX 'SITEMAP' of revision material

Scroll down to find your academic level and science based course

Doc Brown's Basic science quizzes designed for ~11 to 14 year old 'middle' school science students (e.g. revision stuff for UK KS3 science courses, ~US grades 6-8, India upper primary school science)

Lower School Science Quiz Links

Lower School Science - BIOLOGY Quizzes

Lower School Science - CHEMISTRY  Quizzes

Lower School Science - PHYSICS Quizzes

Combined Lower School Science Quizzes

Doc Brown's Revision notes and quizzes designed for ~14 to 16 year old school science students (e.g. revision for UK GCSE 9-1, IGCSE, O level, ~US grades 9-10 science Courses, India secondary school science IX and X - biology, chemistry, physics, environmental science)

GCSE/IGCSE level BIOLOGY Revision Notes

GCSE/IGCSE level CHEMISTRY Revision Notes


GCSE/IGCSE level Chemistry Revision Quizzes

and for UK based science courses:

AQA, Edexcel, OCR (Gateway & 21st C) 9-1 GCSE Sciences Revision Summary links

GCSE 9-1 Chemistry Topic Quizzes to match above specification links

Doc Brown's Revision help for ~16 to 18 year old pre-university advanced level chemistry students - higher school e.g. revision for post 16 UK advanced A level chemistry courses, IB, ~US grades 11-12 (K12 honors), India upper secondary school XI and XII chemistry course syllabus specifications

Advanced A level ORGANIC chemistry revision notes

Organic nomenclature quiz index - naming organics?

Advanced level INORGANIC chemistry revision notes

Advanced level PHYSICAL-THEORETICAL chemistry revision

Selected Advanced Level chemistry multiple Choice quizzes & worksheets

Countries whose students and teachers Doc Brown's chemistry site: United States, Great Britain, India, Australia, Sweden, Poland, Malaysia, Indonesia, South Africa, Finland, Russian Federation, Singapore, Canada, China, Germany, Pakistan, Nigeria, Iran, Hong Kong, Romania, Unknown, Netherlands, Kenya, New Zealand, Ireland, Sri Lanka, Thailand, Japan, Italy, Ukraine, South Korea, Tanzania, Brazil, Philippines, Zimbabwe, United Arab Emirates, Vietnam, France, Slovenia, Norway, Angola, Taiwan, Bangladesh, Brunei Darussalam, Egypt, Zambia, Turkey, Israel, Spain, Hungary, Belgium, Czech Republic, Uganda, Botswana, Papua New Guinea, Mauritius, Saudi Arabia, Namibia, Denmark, Chile, Mexico, European country, Greece, Ghana, Argentina, Switzerland, Lesotho, Austria, Nepal, Rwanda, Qatar, Jordan, Malta, Cambodia, Morocco, Unknown, Ethiopia, Iraq, Colombia, Seychelles, Lithuania, Portugal, Maldives, Peru, Myanmar, Guyana, Oman, Liberia, Fiji, Bulgaria, Kazakhstan, Trinidad and Tobago, Malawi, Guatemala, Sudan, Cyprus, Kuwait, Panama, Cameroon, Jamaica, Lebanon, Virgin Islands (British), Ecuador, Mozambique, Venezuela, Estonia, Bahrain, Croatia, Slovak Republic, Republic of Serbia, Latvia, Senegal, Bolivia, Unknown, Georgia, Barbados, Uzbekistan, Swaziland, Puerto Rico, Somalia, Algeria, Costa Rica, Belarus, Moldova, Macau, Sierra Leone, Solomon Islands, Libya, Curacao, Guam (USA), Bhutan, Dominican Republic, Kyrgyzstan, Syria, Azerbaijan, Bahamas, Belize, Macedonia, Luxembourg, Suriname, Unknown, Tonga, Bosnia-Herzegovina, Honduras, Madagascar, Albania, Haiti, El Salvador, Armenia, Laos, Antigua and Barbuda, Tunisia, Uruguay, Samoa Islands, Gibraltar, Gabon, Yemen, Iceland, Ivory Coast (Cote D'Ivoire), Bermuda, Vanuatu, Palestinian Territories, Northern Mariana Islands, Afghanistan, Gambia, Mongolia, Saint Vincent & Grenadines, Jersey, Burkina Faso, Benin, Cayman Islands, Congo, Democratic Republic of the, Saint Kitts & Nevis Anguilla, Dominica, Liechtenstein, Polynesia (French), Montenegro, Grenada, Reunion (French), Norfolk Island, Sint Maarten, Isle of Man, Equatorial Guinea, Guinea, Congo, Mali, Anguilla, Monaco, Niger, New Caledonia (French), Tuvalu, Faroe Islands, Turks and Caicos Islands, Paraguay, Andorra, Nicaragua, San Marino, Tadjikistan, Togo, Djibouti, Cuba, Mauritania, Virgin Islands (USA)

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Other 'non-science' stuff

Doc Brown's Travel Pictures

CV and 1993 still with beardCV and 2006 still click click!!I hope these web pages of 'Doc Brown's Chemistry'  help your studies! and a warm welcome to the HOMEPAGE of doc b's "Chemistry Online" revision website. This was my millennium 'teaching & learning' project and Doc Brown (teacher) has been online since 2000! Its a big SCIENCE WEBSITE to get to know from a retired CHEMISTRY teacher (and some physics and general science for teaching and learning purposes), SO, use the appropriate INDEXES and Google custom 'Doc Brown's Site' SEARCH too! 'Doc Brown's Chemistry' (all material © Dr Phil Brown 2000 onwards) has lots of  science revision notes & quizzes, mainly an e-learning website for chemistry, but includes some biology and physics too AND lots of 'unofficial' revision summaries for ALL the current English GCSE Science courses

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Doc Brown in action in a Whitby Community College chemistry laboratory (now part of Caedmon College, Whitby) and out in the heather of the North Yorkshire Moors. Note the absence of a lab coat, hence the unseen holes in trousers, corduroy trousers are particularly susceptible to chemical attack!

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IGNORE THESE LINKS to NEW or RE-EDITED PAGES, they are for search engine caches

2024 * Feb 5th ir1 ms1 1nmr1 13nmr1 *  ir2 ms2 1nmr2 13nmr2 Feb 6th  *  ir3 ms3 1nmr3 13nmr3 *  ir4 ms4 1nmr4 13nmr4 *  ir5 ms5 1nmr5 13nmr5 Feb 7th *  ir6 ms6 1nmr6 13nmr6  *  ir7 ms7 1nmr7 13nmr7 *  ir8 ms8 1nmr8 13nmr8  *  ir9 ms9 1nmr9 13nmr9 * Feb 8th *  ir10 ms10 1nmr10 13nmr10  *  ir11 ms11 1nmr11 13nmr11 Feb 9th Graham's law of diffusion calculations porous pot experiments * Feb 11th  ir12 ms12 1nmr12 13nmr12 Feb 12th ir13 ms13 1nmr13 13nmr13  ir14 ms14 1nmr14 13nmr14 Enthalpy of combustion of alcohols   ir15 ms15 1nmr15 13nmr15 Fepage06\spectra\3-methylbut-1-ene-nmr13c.htmb 13th  ir16 ms16 1nmr16 13nmr16   ir17 ms17 1nmr17 13nmr17 Feb 14th ir18 ms18 1nmr18 13nmr18  ir19 ms19 1nmr19 13nmr19 * ir20 ms20 1nmr20 13nmr20 Feb 15th * ir21 ms21 1nmr21 13nmr21 * ir22 ms22 1nmr22 13nmr22 Feb 16th * ir23 ms23 1nmr23 13nmr23 * ir24 ms24 1nmr24 13nmr24 * ir25 ms25 1nmr25 13nmr25 Feb 17th adaptations biodiversity biomass the human brain cell organisation cell specialisation cell structure cell division big bang theory electricity 1  electricity 2 Feb 26th ir26 ms26 1nmr26 13nmr26 ir27 ms27 1nmr27 13nmr27 ir28 ms28 1nmr28 13nmr28 ir29 ms29 1nmr29 13nmr29 Feb 27th ir30 ms30  13nmr30 1nmr30 ir31 ms31  13nmr31 1nmr31  ir32 ms32  13nmr32 1nmr32  ir33 ms33  13nmr33 1nmr33 Feb 28th ir34 ms34  13nmr34 1nmr34 * ir35 ms35  13nmr35 1nmr35 Feb 29th ir36 ms36  13nmr36 1nmr36 ir37 ms37  13nmr37 1nmr37 March 1st ir38 ms38  13nmr38 1nmr38  ir39 ms39  13nmr39 1nmr39  ir40 ms40  13nmr40 1nmr40  March 2nd ir41 ms41  13nmr41 1nmr41  ir42 ms42  13nmr42 1nmr42 ir43 ms43  13nmr43 1nmr43  ir44 ms44  13nmr44 1nmr44 March 3rd Electrolysis Quiz ir45 ms45  13nmr45 1nmr45 March 4th ir46 ms46  13nmr46 1nmr46  ir47 ms47  13nmr47 1nmr47  ir48 ms48  13nmr48 1nmr48  ir49 ms49  13nmr49 1nmr49  ?




The mediocre teacher tells.

The good teacher explains.

The superior teacher demonstrates.

The great teacher inspires.

Quote from William Arthur Ward "Thinking minds"

INTRODUCTION - how you and your students can help!

  • Doc Brown's Chemistry IS A NO FRILLS SCIENCE WEBSITE!

  • I write 'old fashioned' textbook style notes and try to write to the highest academic level needed for a particular course.

  • The pages are written in simple old HTML 4.01 ? and I see no reason to write in elaborate style sheets.

  • The more sophisticated code for quizzes is provided by the free to use (if free to use online) 'HOT POTATO' software.

  • I'm aiming to write a completely integrated chemistry website to cover anything encountered before university (initial encounter age usually 11-18). There will be increasing links, backward/forward, and upward/downward, to aid transition from one academic level to another.

  • What do you, or your students, like or dislike about the site?

  • What country/course are your students doing? I'm UK based and its sometimes difficult to relate to other countries national grades or levels, so can you please help?

  • Suggest improvements? Email any possible Q or revision note errors AND any broken link.

  • The Google [SITE SEARCH] box is dedicated to this site, you can enter whatever key words or formulae etc. - even fragments of equations!

  • Encourage the students to be familiar with the academic level of the web pages.

TOP OF PAGE and main indexes

 The Origin of Doc Brown's Chemistry back in AD/CE 2000 !!!

Doc Brown's Chemistry author's CV chemical history about the website

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Whitby Community College Science Department 1993 (photo © Keith Deason)

Mike Harrison, Keith 'tech' Deason, Phil Brown, Roger Parsons, Mike Rothwell, Effie Andrews, Alan Bentley

John Verrill, Shirley the chief 'tech', Sue Spencer, Pete Wallace, Nick Pike, Joan Lister

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Primary Science Fair "Rockets, Aliens and Star wars"

Whitby Community College Summer 2001

A sort of Curriculum Vitae!

Dr Phil Brown's Education, Qualifications and Experience

  • ()c) doc bHND in Chemistry, 1969 (and gained part I of the GRIC degree)

  • Full Graduate of the Royal Institute of Chemistry, GRIC, London, 1969 (now incorporated into the Royal Society of Chemistry)

  • PGCE post-graduate teaching certificate, St Katherine's, Liverpool, 1974

  • ()c) doc bStarted teaching from Easter 1975 in Shadsworth School Blackburn

  • PhD Physical Chemistry, Liverpool, England, 1976

  • Started teaching in Whitby Community College in 1978, retired 2003.

  • Started website in 2000 - My' Millennium Project'.

'Work Experience'!

  • ()c) doc bIn 1957, out of the final junior year of Whiston, Halsnead Primary School class of 45, two girls went to the Prescot Girls Grammar School, and the rest of us were dispersed to various surrounding secondary schools!

  • I have to say in both primary school and early secondary school I was more interested in trainspotting!

  • Rainhill Station etc. & Steam trains in the 1960s

  • At Whiston Secondary Modern School for Boys, a kind and thoughtful Chemistry teacher, Mr Fairclough, gave a lazy pupil some chemistry projects to do and that pupil started working and never looked back! until retired!

  • After leaving school at 16 I worked in the analytical laboratories of Ward Blenkinsop, manufacturer of fine chemicals for the pharmaceutical industry. At the same time I studied for the ONC in chemistry via day release and night school at Widnes Technical College (now Halton College) in South Lancashire near Merseyside.

  • Also at 'Widnes Technical College',  I was a student on the first HND sandwich chemistry course in the country (1962-1965). It was the best chemical education I ever received with work placements at Berk Ltd, Essex (flame retardant development for plastics), Distillers Products, Speke, Liverpool (analytical analysis) and ICI Research, Runcorn (herbicide synthesis). I'd love to meet again any of my lecturers from that time, I wonder where they are? are they alive!?

  • I completed by GRIC degree at the Harris College Preston (1968-1969, now part of the University of South Lancashire) and had a great life at Liverpool University doing a PhD in the "Pyrolysis and Combustion of Polymers" in the Donnan Laboratories in the Department of Physical, Inorganic and Industrial Chemistry (1969-1973) followed by the PGCE teacher training course at St Katherine's College, Liverpool (1973-1974).

  • I am a highly experienced Science teacher of GCSE Chemistry and associated Earth Science, GCSE Physics and Advanced Level Chemistry. I started teaching at Shadsworth Comprehensive School, Blackburn, in April 1975 and first encountered those dedicated people who keep the education business progressing as well as ticking over.

  • ()c) doc bI moved to Whitby in January 1978 and for 25 years until retirement in 2003, No2 and then Head of Chemistry at Whitby Community College which is a 14-18 'comprehensive' school serving the seaside town of Whitby in North-East England. By the very nature of the teaching job, it will have its ups and downs but working at Whitby has proved overall a most satisfactory 25 years of professional life and I've never really yearned to leave Whitby and the beautiful North Yorkshire Moors.

  • I've been blessed to work with many dedicated and highly competent colleagues over the years in a college that continues to develop and serve the needs of the town of Whitby. The College has now achieved 'technology college' status and the first electronic blackboards have arrived in science and so hopefully, I will contribute to some 'screen' resources! Whitby Community College is now part of 'Caedmon College, Whitby' (Normanby Campus ?)

  • The Salters Advanced AS/A2 Chemistry course was started in 1998 by myself and Dr Sue Morgan (a prior Salters enthusiast) and we both regard the course very highly. The course has a thoroughly up to date approach to teaching chemistry and its modern applications. The course is quite demanding on both students, and teachers! but its a great course and well worthwhile doing.

  • Most of the courses and training I had undertaken in the last years of my career have been directed towards Salters AS/A2 level chemistry and ICT. I' was awarded the UK threshold 'bonus' for teaching quality, the following upper spine 2 point and 2 recruitment points as a bonus!

  • I did not feel particularly old fashioned in my approach to teaching i.e. use of ICT and the 'Salters' approach to AS/A2 Level chemistry. I worked on the school intranet and my 'embryonic' but growing BT chemistry internet website called "Doc Brown's Chemistry Clinic". There are extensive notes and quizzes for KS3 and GCSE Chemistry. The AS/A2 side of the website awaits major development but the organic chemistry naming and structure sections have been highly praised by the Salters team based in York University and represents a tiny fraction of what I can accomplish through this medium in the long-term.

  • When teaching the GCE advanced Salters AS/A2 Chemistry sets at Whitby, all students were on email support. The WCC 'chemo memo' went out every week and all expected to use my main website regularly. They could send homework and coursework to me for marking and correction. In return they get a Chemistry Sunday bulletin for the following week, an "ask Jeeves service" and of course 'reminders' of deadlines! Parents thought it was great!!!!!

  • Although I'm retired (with a little 'r') from contractual employment Whitby Community College, I have no regrets at all about being a teacher, and cannot think of a more worthwhile job in society.

  • Judging from the appreciative response to my website work, I'd better keep going on it and keep on putting new wine in old bottles!!! and its an appropriate contemporary medium to put 43 years of learning and teaching chemistry experience!!! Over 500 other websites back link to "Doc Brown's Chemistry" and there is much work to do particularly on the Advanced Level AS-A2 (US grades 11-12) pages.

  • As well as working on the website for free, I did science supply teaching cover for Whitby Community College, Caedmon School, Stokesley School and Pickering School
  • Also worked on question databases Crocodile Clips-Crocodilia, Promethian and the BBC Bitesize revision site! 
  • I've marked A level chemistry papers for Edexcel and OCR-Salters and KS3 Science SATs.
  • I did do private tuition locally in North Yorkshire and Cleveland areas.
  • I was in The Dalesmen Singers, a  Dalesmen are a male voice choir based in the village of Danby on the North Yorkshire Moors and we perform in a variety of venues and help raise money for charities and church funds.
  • I continually walk the North Yorkshire Moors and visit as many interesting places in the UK and Ireland as possible and all trips are faithfully recorded with a digital camera and all are presented with brief notes via North Yorkshire Moors
  • In 2020 I joined the Stokesley U3A participating in, including giving talks too, the science group and railway enthusiasts group.
  • ()c) doc b Interests

 1st THE FAMILY, quite some time ago!

Becky, Molly, Ros, Me and Mark,

and now we have granddaughter Niamh.

2nd, in any order: Walking (e.g. Yorkshire Dales left), listening to music, archaeology and of course educational chemistry computing as exemplified by this website

VERY OUT OF DATE, new pics soon, but those were the days when ALL seemed young!!

Some of my last Advanced Level Chemistry Groups: Year12 AS set and Y13 A2 set and finally

My last GCSE Science-Chemistry-Physics Class at Whitby Community College 2003 (bye bye 10DE1)

Final mugshots of some of you! Science Set 10DE1 and tutor group 12WPB 2002-2003

Doc Brown's Chemistry: My last ever contracted GCSE Chemistry lesson: (1) revision of the principles of electrolysis via acidified water, collect the gases together under soap solution, apply lit splint!!!, (2) The 'sparky' Thermit reaction (Al + Fe2O3), (3) burning magnesium in carbon dioxide, explain black specks and crackling! (CO2 made from conc. HCl and powdered limestone - just had to revise rates of reactions!), 1st repeat of (1), (4) flame colours from Na, Li, Ba, Ca etc. to explain firework colours and how we id elements in stars, (5) The Harry Potter Dragon experiment ( A NEW ONE!) - igniting floating clumps of natural gas in soap bubbles - brought the house down (fortunately, just literally, ok J K Rowling!), and couldn't resist a deafening (open windows please, hands over ears) 2nd repeat of (1). 

TOP OF PAGE and main indexes

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In using Doc Brown's chemistry website PLEASE FIND YOUR 'nearest' ACADEMIC LEVEL of the three choices above or below and PLEASE explore the ensuing links. You can save and use the MINI-SITE MAPS of Dr Browns chemistry website for each academic level, and also use alphabetical A-Z science site index and most pages have a Google site search dedicated to this site.

The site is written for three broad academic levels, BUT first!

Doc Brown's Chemistry: ALL of the website resources are FREE TO USE ON-LINE as a class resource as long as the pages are NOT COPIED into any electronic/CD/DVD storage system INCLUDING MOODLE, INTRANETS, BLOG SITES or EXTERNAL SCHOOL INTERNET SITES etc. etc.! i.e. anything!

 Doc Brown's Chemistry: None of my own work is to be used or copied in the production of any webpage for the internet or an intranet. I retain all copyright of ALL the content of the Hot Potato quizzes. (Hot Potato is a free software package if your work is made available free online). ALL site content, unless otherwise indicated is © of Dr W. P. Brown 2000+ - I'm a 'one man band'! Sadly, I have already had to contact several schools on breach of copyright issues. I make no apologies for running the adverts - now many years retired from science-chemistry teaching, the revenue pays for the web hosting site, domain name, computers, latest textbooks etc. However, I don't endorse the adverts personally AND I never mix the ads with the science-chemistry. The adverts are at the top and bottom of the page with lots of detailed 'unadulterated' notes between!

TOP OF PAGE and main indexes

"Doc Brown's Chemistry Clinic" website was BUT is now known as "Doc Brown's Chemistry" hosted at and rapidly becoming "Doc Brown's Science" site as I branch out, as well as GCSE Chemistry, into GCSE BIOLOGY and GCSE PHYSICS revision notes too, in other words I'm aiming to cover, at least in revision summaries, all the GCSE science courses. So, PLEASE update your links! The site is free to use on-line, and always will be and seems to work ok on all  iphone ipads netbooks epad tablet android systems NOT in apps format. Contact via How to revise chemistry? What is the best way to revise chemistry for examinations? Exam revision is a chore, and, there is no way round it, but remember that hard work pays off and the biggest resource, apart from your teacher, lesson notes, textbooks, internet etc. is YOUR potential ability to learn, AND developing a positive attitude to study, that enables you to work hard to succeed.

There is no magic revision method - quality time study - this is science not alchemy!

 Doc Brown's Chemistry: Most of the notes are chemistry, suitable for lower school, high school, colleges for pre-university chemistry courses in any English speaking country OR other countries where chemistry courses are conducted in English e.g. Australian chemistry-science courses, Brazilian chemistry-science courses, Canadian chemistry-science courses, Chinese chemistry-science courses, Hong Kong chemistry-science courses, Indian chemistry-science courses, Ireland/Irish chemistry-science courses, Kuwait chemistry-science courses, Malaya/Malaysian chemistry-science courses, New Zealand chemistry-science courses, Singapore chemistry-science courses, South African chemistry-science courses, UK chemistry-science courses (United Kingdom - England, Northern Ireland, Scotland, Wales) USA chemistry-science courses (US, United States of America)

 Doc Brown's Chemistry: As far as I know, my website runs on all browsers, pc, laptop, notepad, netbooks, ipads, epad tablet, android and even the iphone - so I see no reason to write an app or apps for science - biology, chemistry or physics!

I hope Doc Brown's science-chemistry pages will prove a useful and good revision e-learning website for revising AQA, Edexcel and OCR 21st Century and OCR Gateway GCSE Science, GCSE Additional Science, GCSE Biology, GCSE Chemistry and GCSE Physics. Hopefully, eventually! these revision guide summary revision notes will cover all aspects, learning objectives, items of all the topics, units and modules of the AQA, Edexcel, OCR 21st Century and OCR Gateway GCSE science courses. I also hope this revision site offers revision tips and encouragement and hope that you can do well in your exams!

Although Doc Brown's website centres around UK science courses, the study notes and revision quizzes should prove useful for chemistry revision of any science course taken by 11-18 year old school-college pupils-students around the English speaking world. I've tried to indicate the US grade levels and other countries if supplied with the information. The site covers KS3 Science GCSE, IGCSE, O Level and A Level Chemistry AS A2 IB and enables free online student exam revision help notes and practice questions eg quizzes

 Doc Brown's Chemistry was originally written for UK pupils/students aged 11-14:  Quizzes for all science and extra chemistry work sheets, crosswords etc. for England-Wales-NI Years 7, 8 and 9 final biology, chemistry and physics KS3 SCIENCE quizzes revision for QCA criteria science based courses. Also suitable revision help for : US K12 Science grades ~6-8, Caribbean Integrated Science Grades 7-8, Hong Kong Forms 1-3. Doc Brown's Chemistry website was originally written for UK pupils/students aged 14-16:  Revision-research-information notes and quizzes for England-Wales-NI Year 10-11 GCSE-IGCSE-KS4 and 14-19  Diploma courses in Science CHEMISTRY for AQA GCSE Science-CHEMISTRY, CCEA, Edexcel GCSE Science, IGCSE Chemistry, OCR GCSE 21st Century Science, OCR GCSE Gateway Science, CIE IGCSE/O Level Chemistry and WJEC GCSE Science-CHEMISTRY courses. Also suitable revising help for: US K12 Science-Chemistry grades ~8-10. Chemistry of the Caribbean Secondary Education Certificate (CSEC) Grades 9, 10, and 11, Hong Kong HKCEE Form 4 and Form 5, India Central Board of Secondary Education CBSE - All India Secondary School Examination AISSE Class 10 (Class X) school leaving science-chemistry Indian School Certificate Examinations ICSE science paper 2 Chemistry for Class IX and Class X (classes 9 and 10) CISCE (Council for the Indian School Certificate Examinations),  equivalent science-chemistry courses in Ireland (leaving certificate), Canada  United States (US/USA/Ca grade systems), Australia (e.g. NSW school certificate Stage 5), Singapore, Hong Kong, New Zealand and other English speaking secondary school or college courses.

 Doc Brown's Chemistry was originally written for UK pre-university students aged 16-18 UK A AS A2 Level:  Selected revision notes and a few quizzes and structured questions for International Baccalaureate Diploma Programme of Chemistry (IB), UK based Advanced Level CHEMISTRY KS5-GCE-AS-A2-IB-BTEC National awards-diplomas-NQF-GNVQ-NVQ Level 3 for AQA GCE Chemistry, CCEA GCE Chemistry, Edexcel GCE Chemistry, OCR GCE Chemistry, Salters Chemistry, WJEC GCE Chemistry, IB Chemistry and 14-19 Diploma courses in advanced level chemistry courses. It is essentially pre-university chemistry BUT 1st year undergraduates may find some useful 'revision' notes and quizzes. Also suitable revise help for: US K12 Chemistry grades ~11-12, Chemistry of the Caribbean Advanced Proficiency Examination (CAPE) Grades 12-13, Hong Kong HKALE Advanced Level Chemistry, CBSE AISSE AISSCE Class 12 chemistry examinations (Indian advanced chemistry Class XII), CBSE (India's Central Board of Secondary Education) Chemistry Class XI and Class XII and equivalent advanced level chemistry courses in Ireland (higher leaving certificate), Canada  United States (US/USA/Ca grade systems), Australia (e.g. NSW school certificate Stage 6), Singapore, Hong Kong, New Zealand and other English speaking secondary school or college courses.

Note on USA GRADES for using Doc Brown's Chemistry website

US 6th Grade - age 11-12 (early part of UK KS3 Science)

US Middle School or Junior High: 7th Grade - age 12-13; 8th Grade - age 13-14 (later UK KS3 Science)

US High School (although some larger schools include 9th with 7th and 8th to make a Middle School)

US 9th Grade - age 14-15 (commonly called Freshmen); 10th Grade - age 15-16 (commonly called Sophomores) UK IGCSE/GCSE Science level)

US 11th Grade - age 16-17 (commonly called Juniors); 12th Grade - age 17-18 (commonly called Seniors) UK Advanced Level Chemistry)

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 Doc Brown's Science Website


Hey doc, loving the chem website. I can safely say it’s getting me through A Levels. Thanks Joshua


Hello, Doc Brown! Just wanted to express how thankful I am for your chemistry revision website; your's are the only explanations that I understand completely. I truly appreciate and love what you do to help others. 

YOU'RE A LIFE SAVER Sincerely, A Very Grateful High School Student (W.W from US)


I used your revision website last year and they helped me get an A* in all three sciences. I deeply appreciate the effort you have put into it. Oliver

Hi! I am a Year 11 student in England, currently studying Chemistry for GCSE (AQA). I just wanted to say thank you for helping me, through your website, with many difficult tests and homework assignments. The entire website is thorough and precise, and it must have taken a lot of work to get it running, and a lot of work to keep it updated; thank you for all the effort you put in! Yours sincerely, Maddison

Hi! I was just using your website for my revision and thought that I should find some way to thank you. So halfway through my revision, I decided to find a way to contact you and thank you for making the website. The website is just so AMAZING. Looking through the textbook and the notes given by my teacher is just not enough because there are missing gaps in explanations which makes harder for me to learn! But the website includes such detailed explanations that fill in all the gaps of the textbooks and notes that I have. This helps me to understand the concepts completely and remember them well. I am so thankful that I have an access to such a useful information for free. Great to have such a reliable source, no more worries. THANK YOU VERY MUCH FOR ALL THE HARDWORK AND YOUR KINDNESS!!!! ~shu, doing CH 101 chemistry course in US, doc b

Docbrown is a really useful web site for the college studets like me&university students who are doing chemistry worldwide. I should thank for your notes doc b staff.  Nice work and wish you all the best to carry on your social works. I wish could donate you something. So I feel I owe you when I clear my doubts on chemistry using doc b notes. :)Thanx doc b. (Y)  Ruchira Subhashana

Hello, My name is Raj and am currently in year 11 studying for my triple science GCSEs, sorry to disturb you as I have neither a question nor a query, instead I just wished to say thank you. It is obvious that a lot of time and effort has been put into the website and I just wanted to let you know that it is much appreciated by all, even if people don’t say it enough. You have helped me, and needless to say hundreds of the students find their way around everything from carboxylic acids to dendrites and for that I am thankful. Your website has saved my skin many a time ( even if it is a bit hard to navigate sometimes)! And I just wanted to let you know that your expertise and knowledge has helped us all understand a little more about the world around us. It is clear you have a strong passion for science and I can think of nothing better to do with it, you are truly an inspiration to me and any other budding scientist who have stumbled across your website in a time of need. I wish you all the best luck for the future and hope you continue the great work!

Thanks for your help again, Raj Doc Brown,  Your website is perhaps one of the most useful revision sites on the internet. Bitesize does not compare. Solely down to this site, I have exceeded scores of 95% + on all of my science exams (Year 9). I was wondering if you'd be able to consider adding multiple choice quizzes for GCSE Physics and Biology. This is probably a lot to ask for, but I know it would help so many. Many thanks, Rhys

Hi, I was looking for info to support my daughter when she was struggling and found your site. It is awesome! If only I had this 30 year ago it would have been such a help for
physics and chemistry! I have bookmarked your page for Phoebe.I have no idea why you have gone to this great effort to support young kids it must be immensely time consuming! I just wanted to say I'm glad you have taken the time and a BIG thank you from a parent. Now if only you did Maths .................... :) Tuula (mum)

Dear Dr Brown, I am currently doing an assignment of the effects of e-waste and how mining to make modern technology affects the environment. I found this
site very helpful and just wanted to thank you for your knowledge and for making a helpful, understanderable website. I have highly recommend your website to my classmates. Thank-you, Jessie

Hello, My name is Ewan and I'm currently studying Chemistry at College in preparation for a Biochemistry course at the University of Edinburgh in September. I'd just like to say that your site has been a great help to me - especially your hydrocarbon section (the list of general formulas for the homologous series was appreciated!). The quizzes also help and it's written in a way that is easy to read. So, many thanks!

Just emailing to say thank you for your excellent science website. I am mum to a grade 9 student and for the last two years he has been doing a lot of exam revision using your interactive science website and has achieved good marks in his KS3 science exams. I wish the resource had been around when I was young. Thank you again, A Thompson

Good website! Keep it up and try to introduce A.t.p.section too. Sent from my iPad !!!

Dear reader, I've just noticed the email button on your website so I thought I'd send you a message. As cheesy as it sounds, the material has helped explain a lot and the concise manner of you notes has been brilliant as it is exactly the way that I try to write them too. You also seem to be the only free online site that caters for all the exams boards (I'm from Wales so this can be an issue). Thanks for your notes, I hope you keep them up as this is truly the only way for me to learn and I have almost taken to copying out your words to cement them in my brain. I've shown others your site but I think they didn't appreciate the simplicity and thought that the simple layout was because of a lack of web design experience (although not as professional as other sites, I don't think you need to be. I've had a look at web design and it was awfully hard so keep it the way it is). One thing I would say is that I have found some of the links odd. I have clicked on links to go to A-level revision bits and was re-directed to their GCSE equivalent. I think that it would be better if you had the A-level links directly and a little link at the top of the A-level notes to the GCSE ones if someone wants to learn the basics of the material. Apart from that slight criticism which I hope was constructive, I have nothing but admiration for your generosity in helping me with revision. I'm not really sure if this will get to you or if I'll get a reply (you don't have to if you don't want) but know that your work is appreciated. (Its pretty late now and I've done enough work today so I'll sign off here) If you have any queries about what I or others think then feel free to ask. Thanks, Gergo

I just thought I would add a note of appreciation for your site which is obviously a labour of love.  I am a sort of lapsed chemist (I have a PhD in the behaviour of the Rare Earths in the melt phase) but I have worked in the energy industry for 30 years and the last real chemistry I did was remedial tutoring for my wife's degree in conservation nearly 20 years ago.  However with children reaching GCSE and A level I needed to work out what I should be teaching them to help rather than hinder and I found your site which is by far the best on the web (if not exactly the most beautiful) which not only let me work out what they should be learning but also gave them a really accessible focussed resource they could use to support their classroom work - I have recommended it to loads of people in the same boat.  Very well done and a big thanks from the Sultanate of Oman - so you can add another country to your burgeoning list.

Regards, Peter Bedson 

Dear Doc Brown, I just wanted to say a big thank you for your really useful online resources, they are a big help to me as I going over some old science materials in preparation for a postgraduate study in environmental policy - the quizzes and worksheets are certainly making, going back to basics really interesting, fun and interactive. Thanks so much, Jennifer hello, I'm Korean high school girl, Moonsun Park. While I was searching in Google for my school work, i found your website. I was in study of metal reactivity series. Your website gave me a lot of help. thanks Dear Dr Brown, Thank you for your fantastic science revision website that you have made availed for free. My daughter in year 7 has benefited a great deal from it and enjoys doing the questions after each topic. Thank you for your contribution to education. Best wishes, Siv May I just say how much I appreciate your fine work creating and maintaining your site. My sons have found it great assistance in their studies and I find it very helpful relearning my own long forgotten Chemistry when helping them. Thank you, Rob Dear Doc, What great work you have done here. I have used your pages as links for our schools new Moodle site as the notes are clear as quiz sheets are very handy. We have recently had some bad earthquakes here and school was closed for over two weeks. I hope my students make good use of your site to catch up on lost time. Regards AS, Burnside High School (Christchurch, New Zealand).

Hi, How are you? I would like to thank you for your great website and it has helped me complete my AS level chemistry exam. Thanks again. Rob Dear Doc Brown, Can I just thank you for the magnificent resource which is your website. I teach A-level Chemistry in Cambridge and am so grateful to find that selfless people have provided such useful, high-quality material. Yours sincerely, Andrew Dear Dr. Brown, I just wanted to say thank you for your chemistry website. I'm looking at a career change into teaching science & chemistry following a redundancy and while my background is environmental sciences and I've been one of 2 Welsh reps on DEFRA's UK Chemical Stakeholders Forum for the last few years, I'm the first to admit that there are areas I'm rusty on. I know my knowledge needs to be at least AS level in all 3 sciences if I have a hope of starting a PGCE in September and I've started working through the exam boards' detailed requirements. Finding your online resource was a godsend. With both me & my husband out of work, I need free access to the detail to help me work through the areas I need to polish up. Thank you for giving me the tools I need to get onto the next step. All the best, Amy

Dear Dr Brown, I want to start off by expressing my love for your website, it has proven priceless for my Mock GCSEs and GCSEs which will be done this coming Summer, and also hoping to go into Medicine; I am sure your A-Level Chemistry section will do the same. A suggestion that I have is that you make video tutorials, maybe like 10 minutes on one small topic. Chemistry being a subject where you HAVE to understand it well to be able to do it, something that I still find extremely hard to this day (mole calculations, titration calculations will be the death of me... :) ) One finds that when being taught it through the voice of someone who REALLY knows what they are talking about proves a lot more helpful than reading your notes, although your notes are pretty much perfect. Just a small suggestion, but if you would want to, I would be glad to tell everyone i know about it. Many Thanks for all the help you have given everyone, truly altruistic. Yours, Abdullah Jawad. Hello, happy new year, thank you very much for your site it is very useful! Rebecca. Dear Dr Brown, I am working as a medicinal chemist in drug discovery phase. I would like to thank you for providing such a vast pool of information in a very clear and understanding manner. It helps me a lot in learning the basic aspects of organic chemistry. I really enjoy reading your notes and lectures. Thanks & regards, Neha Singla, Sr Research Chemist, Medicinal Chemistry Dear Doc Brown - I am a teacher in a rural school (no facilities like no library and no computers) in South Africa where I teach natural science to grade 8 and 9 Zulu and Xhosa teenagers. I am loving your States of Matter quiz - its really helping me to plan my lessons. Particularly helpful as the children don't have books so I will be able to challenge them on the board with your questions and diagrams. Thanx a lot, Best wishes, Marian Ross Love your pictures of Lealholm and the surrounding area. It feels like I am home when I look at your photos. Thank you for all your time and effort! Lori Hello doc, how are you? I would just like to say that your website is very helpful at feeding me knowledge. Please put more and more quizzes and revision tests on there as they are extremely beneficial to my learning. Thank you, Tom  

Dear DocBrown, Me and my fellow pupils would like to bring to your attention that you are in fact, a legend. Your website is the best thing I have ever seen, and has allowed us to complete our chemistry coursework research early. (20 minutes in fact, so we have time to play jumpers for goalposts). So, to summarise, you are a legend, keep up the good work, and we love you. Lots of love, Churston Year 11 Chemistry. Hello Mr Brown, I just wanted to email and thank you for the help that your website has given me! I found it really helpful, so thank you very much for putting this out on the internet for lots of children to use. Yours, Chloe great web-site! I do some private tutoring, I've a chemistry degree and helped my non-scientific son with his igcse and carried on tutoring. I often have a look at your site for help. Thanks, Rosemary Just wanted to say thanks for creating this website as using it me and my friend have finally managed to crack titration calculations! Kay Hi, My name is Glenda from Australia. I have just been looking through some of you photos of Ireland and wish to congratulate you on a job well done. It must have taken a lot of time and effort to do so well. I have been going through my photos from our recent trip and looking at your photos have brought back many happy memories. Regards, Glenda I just wanted to thank you for the amazing revision site you have created! if i pass my exam it will purely down to the info i have learnt from the site :) it's so well set out and most of the info is concise enough to learn quickly and effectively! just thank you for all your help! elody fumi I am just emailing to say Thank you. Your site is by far the most useful to revise from. The diagrams are easy to use and I will strongly recommend this to my other friends that may need to use this site. Thank you very much, Jack Dear Doc Brown, My son is currently taking his GCSEs. My I congratulate you on your excellent website which almost made revising Chemistry fun for Alex. I wish there were similar websites for the other subjects. We were discussing your website with my younger daughter (14) who, I am pleased to say, has already been directed to your website by her Chemistry teacher. Thanks again, Lynn hi i just wanted to thank you for making that website u have saved my life thank u so much, Ali Agha Doc Brown, Just like to say a massive thanks for this great website you've created. The quizzes on chemical calculations have saved myself from a lot of trouble in my final exam and the notes on sulphuric acid have taught me more than my chemistry teacher this year. Again a big thanks for the help! Yours Joe, A very grateful student!

This is a great website. Can you expand it for other subjects e.g. French? Watkin39 You must be joking! Thank you for making such a clear and comprehensive set of notes. I'm really a mathematician, but find chemistry interesting and found myself tutoring it as I live on a small island and any help is better than no help! I have been trying hard to find background info to make sure that I know more than the students need to know and I think your site is exactly what I need. That is why I am so grateful. I hate to feel that I am bluffing my way through anything and your site answers all of the questions that I have, before the brighter students quiz me. I am still interested to find out more, but at least I feel that i am doing the best for the students I have for now. Well Done! Dawn Hi Doc Brown, I would just like to thank you for your amazing site. While I was a student preparing for my A levels I used it. Now I’m training to become a teacher, I direct my classes to your website for help, and for the quizzes. Many thanks for all your hard work which you must have done and still do. Laura Dear DocBrown, You are an amazing person. I truly found your site a boon. I had quite a lot of Chemistry problems - but , by using all the tools and notes in your site, I have become the best Chemistry student in my school. Thank you so much for all that you have done for me and student like me all around the world. I was quite surprised that the resources your site has are for free! that is very generous of you - yes, knowledge is priceless. It has such concise yet detailed notes. I am very grateful to you - I hope you have an excellent New Year. I am doing my GCSEs in 2009 - I would like to request you for some physics notes. Please, it would be a great help. I await your reply. I respect you dearly sir, thank you for all that you have done for me, Yours Sincerely, John, GCSE Student from Kansas Thanks for such a wonderful site! It's helped me through some difficult times and continues to aid me in my revision. Thanks again, Kieran (CCEA student, NI) Hello, This is indeed a very interesting website for students. I wish to thank you for providing such clear explanations and diagrams for students to cope with their chemistry concepts. Regards, Salina Doc Brown, I am currently tutoring Edexcel IGCSE Chemistry (4335) and have found your site invaluable. I also think the IGCSE course is excellent, so much more exciting and demanding for able students, than the modular GCSE Science courses. Today I was reading through your site for probably the hundredth time, when I found the first typo. Exercise 13.2.2 when calculating moles of Copper needs a division sign, instead of the number 7. I think your site is ace and I am so, so grateful for all the time and effort you put into it. I wish one existed for other subjects. Kind regards, teacher, Surrey Dr Brown, Your website is the heaven on earth for Chemistry students. As a father of 2 IGCSE students I can see the ultimate use of this site right from understanding the concepts, revisions, multiple questions etc. I appreciate your hard work and quality of the site. Keep it up, Regards, Ponduri Dear Dr.Brown, I am an 18 year old student form Malta (Europe). I just wanted to thank you for the great site you put up. It is really interesting and well planned. It is helping me a lot in my studies as the notes i got, unfortunately, are not so good! I thank you again. Stephanie, Malta Thank you so much for having produced such a fantastic revision/homework site. My daughter narrowly failed the 11+ (which we still have in our area) and now goes to a local school which is rather poor academically (a specialist sports college!). Some of the lessons are very disrupted and she finds she has to teach herself a lot at home. Thank you for making your site freely available. I don’t know what we would do without such sites. Liz thanks for making the website, it really helped me with my sats revision, melissa Just wanted you to know that 8C2 are enjoying using your multiple choice quizzes in preparation for their end of year exams. Terrific website - wish it had been around 30 years ago when I was revising! Thanks A. Wright, Licensed Victuallers' School, Ascot This is a great sight. I am teaching science and not a science teacher and your sight has helped me immensely. Thank you. Libby, Australia Hello Doc, Your website is great. I am very happy I found it, I have been struggling to find more interactive reinforcement and skill building activities. Thanks for sharing with others that are not as technology savvy as you are. I love the quizzes. Thanks, Karol, Chemistry teacher Doc B: Ran across your website today and just wanted to say thanks and WOW … great accumulation of all your learning and teaching over the years. It demonstrates just what a fine educator you are. Congratulations, and thank you. Steve, Maths and Chemistry Teacher, Bellevue, WA, USA Doc Brown, I am revising at the moment for my AQA Chemistry GCSE and I would just like to say how useful your site is. It is very clear and things are described concisely. Please keep up the great work as all the information has been invaluable for me. Many Thanks, Stuart Hello. Love your photos of Dunmanus and Bantry Bay. We were there on holiday when you took the photos last year. Where is Toe Head? We are not familiar with that view. Thanks for brightening up a very windy Bank Holiday Monday, Pam and Rod

WOW! HELLO,I AM A GCSE STUDENT AND MY GOD, YOUR WEBSITE HELPED ME SO MUCH!!! I USE IT EVERYDAY AND I LEARN EVERY TIME I GO ON IT. YOU TRULY ARE AMAZING. HAVE YOU MADE WEBSITES LIKE THIS FOR BIOLOGY AND PHYSICS? DOESN'T MATTER IF YOU HAVEN'T AT THE MOMENT BECAUSE I ONLY GOT MY CHEMISTRY EXAMS ON THURSDAY 22 NOV. ANYWAY, YOU HAVE HELP ME SO MUCH AND I CAN'T THANK YOU ENOUGH. BEST REGARDS, AHMED Hello there! I just wanted to comment on your web-site. I had a motorcycle accident a few weeks ago and had to miss class at college (I'm in my second semester of medical school) and consequently fell super behind on my organic chemistry classes. Well, up until yesterday I had no clue how to identify alkanes, alkenes or name alcohols, and I have a test on this coming up Tuesday. Anyway, I have to say I was completely lost in my chemistry guide until I found your site. I'm repeating your quizzes over and over and by trial and error I'm learning how to identify the structures. I'm so happy! Now I can actually draw the structures on my guides' 'practice' pages. I hope I do good this coming Tuesday; at least I'm way more confident! Thank you so much! Your page is the best! Melanie Great, easy to understand delivery of info. Well done and thanks! Jo (Mum of 12yr old boy with homework...) Dear Doctor Brown, I am currently a trainee teacher, having recently finished my chemistry degree at the University of Liverpool, and would just like to let you know how useful I am finding your website, to help me write lesson plans and update my subject knowledge. You're doing a great job, and many of my friends on the course think so too. Thanks again, Jennifer Hi, No mistakes spotted – I just wanted to say thanks! This website is so good – got titrations totally sorted now, thank you!!!!!! Beth Dear Dr Brown, I think your site is absolutely brilliant. It is clear, easy to work through, good range of questions, answers supplied….fantastic. Thank you so much for taking the time to put it all together. From Ed, a very satisfied user Hello, I felt that I just had to email you in order to thank you for the excellent science revision site you have created. My son is taking the first module of his science GCSE on the 22nd November this year. This has been rather a daunting prospect for him due to him only being in year 9 (age 13)! I really feel your site has helped him to relax and ENJOY his GCSE revision. Using you superb quizzes and worksheets have helped him prepare confidently for his forthcoming examine. Thank you so much. Kindest Regards, 'a mum'

THANK YOU SO MUCH!! your website has helped me so so so so so so much! My teacher is now quite impressed with all these new answers that i am sprouting out!! THANK YOU! Charlotte

Hi Dr Brown! I just want to thank you for the work you have done in Chemistry. This work has helped me to teach chemistry in a meaningful way to my learners. Keep it up DOC. From D.S.Siyaya in South Africa  

Hello, I emailed you a few months ago regarding a few questions about your website and would really like to thank you for the help and support your website gave me while revising for my GCSE's. I got A* A* for my science double award yesterday so i am very pleased and grateful to the resources which helped me achieve this grade, thanks again, Emily

This is my first semester doing chemistry again after 20 yrs. I can say that this site is remarkable. As I learn to move around and explore the vast collection of information, I am becoming more and more confident. I am quick grasping new concepts. Your site provides information at a variety of different levels. Thank you so much, Helen Dear Doc Brown, You probably get this all the time and even consider it annoying. But I am currently doing my GCSE's and your chemistry clinic website has helped me so much, I don't know what I would do without it!! I am so grateful for all the time you spend on this website, because I feel that it has helped so much. Thank you once again. Yours Sincerely, Natasha Dear Doc, I am a science teacher. Your website has made life so much easier. I’d like to thank you for making science fun again. I am less stressed, more prepared and can tap into your bank of excellent resources when setting cover work. Your site is a God send, Your grateful colleague, CJC. Thanks to your website it helped me study for my pre-midterms exam in organic chemistry this Saturday, July 28, 2007... I'm a 2nd year student of bs chemistry.. I'm from the Philippines.. God bless!!I would just like to say thank you for making such a fantastic sight! I really found it helpful and I now feel a lot more confident about taking my SAT'S exams well the science exams anyway, hope the sight continues!! Jennifer Your fantastic website: Hi there, I am studying Chemistry in the evenings at Birkbeck and wanted to take the time out to tell you that your site is outstanding. I have struggled with acids and bases up till now and find your site easy to navigate and understand. Cheers, Leon. Dear Doc Brown, I want to thank you as I have learned so much from your web site. I am a mother of a grade 9 and during exam  week I had so many over at the my house studying. I used your notes to help them. Sincerely, a mother. Hi Doc Brown Thanks for a great web site. Its very helpful to me struggling away in a small school on a ship in Monrovia, Liberia. George Hi Doc Brown:- Thanks for a great web site. Its very helpful to me struggling away in a small school on a ship in Monrovia, Liberia, George Hello. I found your webpage very good indeed, especially the immediate answer and score results at the end. Although I looked at it to see if it would be helpful to my daughter taking her SATs next week, I soon found myself hooked and wanted to do quiz after quiz. Do you do the same for maths and English? (no time and not my specialist subjects, especially the English!)

Thanks so much for your help. The site is so good. I learning so much and you make it interesting. I like the diagrams they help a lot. Sincerely Nancy Higher modules are so hard to find good resources for so this site has been VERY VERY helpful and helped me get my all A's n my chemistry module tests!, thank you. Lesley Dear Doc Brown, I'm currently an upper sixth student trying to get through his A level Chemistry, with a view of studying the subject at university (I've already got a few interviews). Tonight I was using your site to help with my naming of aromatic organic compounds. I'd just like to say thank you for making your excellent notes available online - they're accurate, easy to follow and extremely helpful. It's obvious that a lot of time went into making the site, and I'd like you to know that your efforts are extremely appreciated. Keep up the good work! Thanks, Aled Hello Phil, I want to thank you for your advice, its very useful and I will definitely take it on board. I'm very surprised that you replied back, I also want to thank you for taking time out to reply to my message. I want to congratulate you overall, because your website is very, very useful. Thank you once again, God bless Karen Doc, you are a true legend. you taught me at Whitby for 3 years and you continue to (even though I am 35 now). you were a fab teacher back in the late 80's and it seems now your reputation is now worldwide!! seriously thanks for all the work you put into this site. it is truly the best site for both teachers and students. you continue to make a massive impact on my learning and on those i teach. many thanks doc. Chris (now head of science!) I love using this site to study it helps me pass all of my science tests. My name is Darrius and I'm 13. Just so u would know I have this page marked to my favourites. GOOD JOB ON DOING THIS SITE

Dear Doc Brown, Just though I would say a big thank you for all of the help that your website has given me. It is incredibly kind of you to put all those resources up there and all so relevant. Thank you for your time and it has really helped during my chemistry coursework, when can you get some Biology and Physics coursework details up there!? Thank again, Rishab

hello doc b, your website has really helped me get high scores on my science. now i love science, all thanks to you!! THANKS!!!!!!!!!!!!!!!!!!!!!!!!!!!!! xx Delia

Hi Doc Brown, I first discovered this fantastic site about 18 months ago. I was looking for something to help my son with his GCSE Chemistry - he prefers on-line to books. (Fingers crossed that all that time spent on-line will be rewarded when the results come out later this month). He is taught at home and, with the help of a distance learning course, I adapted enough experiments to make them suitable for doing in the kitchen with easily accessible chemicals/equipment. This coming September (06) I am repeating all this with a small group of home educated teenagers (Yr 8 - 10). They think chemistry's all about big whizz-bang experiments. Hopefully with the help of your website I can show them that the theory is just as much fun. Thank you for allowing teachers and students to print off quizzes, worksheets, etc. I was dreading having to make my own. Please keep up the good work. This is the best chemistry site I've seen. Lisa

4 Months ago I was a D Strident in Triple Award Chemistry, then I discovered your site. I received an A today. Thank you very much. Shrey

Dear Doc. Brown, We would like to say thank you so much for your website it has helped us so much. We are just going into year 11 and are doing triple science, we struggle with it quite a bit especially chemistry and biology. One of our teacher told us to take a look at your website to see if it was any help for our course work and our homework for the 6 weeks holiday, we would just like to say thank-you so much as your website has really helped us soooo much we now understand the subjects we are studying such as "rates of reaction" and "catalysts". We had to say thank-you so we have written you this e-mail. Hopefully we can now go on to get good grades and be able to study for the jobs we wish to have in the future. We shall continue to use your site. Thanks again!!, Sincerely, Annabel & Lauren

Good Morning Doc Brown, Once again I feel it is only right to e-mail and say a huge THANK YOU for all the wonderful resources that you provide for KS3 and beyond. Without this excellent web site I am sure that as a state school we would not have hit our LA target for science '06!! Take care and know that across the country there must be many teachers like myself who regularly use the web site and are somewhat slow in giving thanks and appreciation! God Bless, Regards, Sarah I just thought that I would let you know how much your site helped me. Before discovering your site I was so stuck I was practically failing science, but with your concise, clear and simple notes I grasped the concepts with such ease. Thank you for the help! From Emma

wow - That's such a quick response - thank you. Would love to be added to your newsletter email list. You are doing a terrific job - keep it up! Thanks again, Many thanks, a frustrated teacher, P.S. have used you site a lot and think it is totally fab - a real life line! Anna

Thank you so much for your chemistry site!! it is so much help and i simply love it!! It has helped me so much in chemistry, hopefully i will definitely gain my A* at GCSE! i will definitely be coming back to the site for guidance and hello when i take my chemistry A - level! Your work is not unappreciated!! Thank you, A grateful GCSE student, Leanne

Dear doc Brown I'm a trainee teacher and I'd like to tell you how fab I think your site is. As an non-chemistry specialist who is required to teach chem, I love using your site to check my subject knowledge and get ideas. It's a wonderful resource. Thank you!!!!! Rachael, PGCE Student, Southampton

Hi Doc, Thanks for the good work done. I just found this website and it's just brilliant. A great contribution to science education. Well done! Robert

hi I am a yr 7 student who was introduced to your website by my science teacher. I love the website and think its excellent. my mum and I are racing each other on the computers. however, I was wondering if you could do some different subjects like maths or English or French, as this has helped me with my revision. I was also wondering if you could do a KS2 website for my three younger brothers. Thank you for taking the time to read this email and hope you will find the time to answer it. yours sincerely, Florence

Hi, I think your website is really brilliant. I have told all my friends revising this GCSE Edexcel Chemistry module to visit you website, only one problem with it why don't you also do it for the biology and physics modules then it would be perfect. Cheers, Eddy, PS Does the module simulation match up to the real thing? doc b. Well they seen to be just like the real modules and they tell you after each question where you went wrong and which are correct and it gives you an idea of how well you've performed, but i suppose the real test would be next Wednesday for the real thing!!!. well all the time and effort into your website is excellent and keep up the good work, Eddy (1 happy customer!!!!)

Dear Doc Brown, I wish to say thank you for your great site. I am teaching GCSE Chem in USA, and as the only chemistry teacher and a long time since I did Chem, I find your site invaluable. Thank you again, Sarah

Excellent site, Thank you, Dan.

This is an excellent source of revision, and the best thing is that there is such a variety and different formatting of the questions (redox-volumetric). zohra, A2 chemistry student

Just to say what wonderful, very helpful site this is. I've just started my A2 revision for Salters Chemistry, and this site is invaluable. I used it last year at AS, and I don't think I would have got an A without it. Thank you very much. C Young

Hello, I am writing this email, to say how much this website has been of use to me! I am doing my Gcse's, and its great for all higher chemistry work, please may you make a website on other subjects, that would be great! gcse student

Just wanted to drop a quick email to say how useful I have found your website in revision and general edification. I am going to be studying chemistry at university (hopefully Durham) and throughout my A level course have constantly referred to your website for information and help, and for general interest as well. Thanks! Yours gratefully Edward, St Albans

Dear Doc B, I received my GCSE O Level results last Friday. I managed to attain 6 distinctions, with an A1 in Chemistry. Thank you very much for your site, I appreciate your well thought-out notes and exercises, they most certainly helped me garner that much sought-after grade! Cheers, MY Wong (NAM)

Fantastic site!!! Its helped a great deal to understand rates of reaction more thoroughly. I'll be using this site more for revision!! Thank you once again. May!

Hi Doc just like to thank you for your excellent work, it really is an extremely useful site for students and teachers. thanks a lot, Jamila

KS3 quizzes - Fantastic stuff; I don't know where you find the time. Thank you again for a brilliant resource. Cheers, Simon (teacher), (doc b: I'm retired with a labour of love!)

Hi, this website has got everything and I'd like to thank you so much. I wish there was a Biology and Physics version! It has Higher parts and extended stuff and it's brilliant. I can tell my teacher has been printing off your sheets and giving them to us! Thanks again, Gowri

Dear Sir, Your site is way cool and has helped tremendously because I lost my notes and need to retake my modules. Thanx a million!!! Regards, AS level Student

hey! jes wanna say gr8 big thanks 4 ur website. i h8 revising from books n it jes puts me off-this has certainly helped! thanks a million. I am due to take resits for some modules in march and now i don't have to rely on the teachers textbook. thank you!!! wish me all the best. Maria

THANK YOU DOCTOR BROWN, YOU REMIND ME OF MY CHEMISTRY TEACHER, YOU ARE THOUGHTFUL AND 'OTHERS-CENTRED'. THIS IS SUCH A USEFUL WEBSITE FOR US 'CHEMISTS' TO USE IN BATTLING OUR JUNE EXAMS, Aribim (I am now retired so the stress levels I shared with students are somewhat down-sized these days, but I'll keep the  Salters pages going!)

I'd just like to thank you for an absolutely great site. it beats every chemistry book my school forces upon me. Thanks again. Evan

I have been on your site and i found it very, very good. my friend thought is was good too YOU ROCK, HAVE FUN WITH YOU REACTIONS. Kit

What an excellent, helpful website. All my students use it, thank you for making it freely available. Edward

Just to say, Great site! - makes an interesting browse whether there’s a need or not! A mixture of work and pleasure! Cheers, Dave

Cool site. It's been very useful in notes, tests, revision etc. Thanks a lot. Sam, Zimbabwe

Dear Sir, I am currently working towards my mock GCSE's next week as well as my final GCSE exams in June, and I thought that I would drop you an e-mail to say that your web-site is fantastic and the best on the Internet! Your web-site provides a superb range of revision notes, which are then accompanied by quizzes. This combination makes the revision process a lot easier and a lot more thorough. Thank you! Yours sincerely J. W

Dear Dr. Brown, I would just like to say that your site is amazing, it helped me gain an A* in my GCSE. I am now doing AS and your site serves as a great reference, Thank you so much. Regards, Prashant

Thank you for providing this wonderful and tremendously helpful and exciting site. I have really enjoyed working with this. Again, thank you. J D L 8th grade Science teacher, Texas.

Hey, I just wanted to say thank you so much for your amazing chemistry website... I was looking for something like this to help my younger sister out to prepare her for her GCSEs, and this was just the thing that we needed. The site is fantastic and has everything we need to prepare her for her upcoming modules. I especially like the MCQs and the fact that there are loads of alternate but similar questions which helps her get familiar with topics and learn proper exam technique. Once again, thank you so much!! Keep up the good work!! Best regards, Maria

This is a fantastic site. I am a chemical engineer trying to help my wife who is taking a chemistry class pass it. This site helps. Thanks, Jim


Thank you for making notes on the rates of reaction topic.. it has helped me so much. I would hate to think where I would b without it. I've got to write an evaluation now.. so maybe a should celebrate so soon. Many Thanks! Owain

Hi, I just wanted to say a HUGE, GIGANTIC, COLOSSAL thank you for making this brilliant masterpiece of a site and making it free for access. I just love all the stuff here and my primary revision material was from here and not surprisingly (because you have such 1st class material), I came out with two A*'s (I did Double Award Science). So thank you SO much. Ally

I just wanted to thank you for having such a marvellous site and for making it free to access.  Your GCSE Chemistry revision notes were much more helpful than the textbook that was recommended by my college. The quizzes were very good and I think that they probably helped me more than anything else to understand where my knowledge gaps were, fill them and then make sure they stayed filled. I've just got back from picking up my results and I got an A in Chemistry and I think that is a lot to do with using your website. Thanks, Claire

Your site is fantastic. Really useful for all of my exams i have taken !!! Is there any chance that the design of the website can be changed in anyway? You have so much great content now that it is beginning to look overcrowded and it takes ages to find what I am looking for. (just a suggestion though!) You have everything I need and more! Daniel (I'm working on the colour, crowding and navigation AND the alphabetical index should be a great help)

Doc Brown … I would like to say a HUGE thanks for making this website, you’ve made my revision so much more fun and easier to revise! So THANK YOU! Marc in Bradford

Just a quick note, obviously its the night before my paper 2. I found your site a few weeks ago and used it for all my revision for both papers, its much better than rummaging through all my papers and books. Just like to say how helpful its been, thanks a lot. Brian

Hi, I've just been using your chemistry site. It's such an excellent resource. Thank you so much for creating it, there's just so much content. Just thought I'd say thanks as it's come in very handy in my A2 coursework which I'm doing at the moment. Pete

Dear Doc Brown, I’ve just finished my first year of reading Medicine at Nottingham University. This is a very belated thank you for all of the time and effort that you have put into your Salter’s Chemistry Website. I was registered at a school that was so poor I attended only to take the exams. Studying independently for my A levels wasn’t the easiest thing to do. Your help  was invaluable in achieving this. Many thanks again. Here’s hoping that you’ll retire from your retirement one day! With kind regards, Jane

I just wanted to say a big thank you to you really, your site has been really useful to me with my revision; its very organised and lays the units and makes what is required of you crystal clear. If only all teachers were as motivated ay! Thanks again, it really decreased my panic levels. Lucy Anne

Hey there it's Hannah and Sarah we just want to thank you for some great revision notes - there  better to understand than the text book! Thanks again, Hannah and Sarah

To Doc Brown, I just thought I would write and commend you on the fantastic website that you have enriched my learning and my teenage life with! I found your website by chance when I first started studying chemistry a year ago, when I used Google to search for information about electrolysis. After finding doc brown's chemistry clinic I needed to look no further. Since then I regularly refer to those pages of wisdom for help in anything and everything - homework assignments, revision or just trying to gain a better understanding. I have also told all the chemistry students I know about this wonderful gem and they see it as a treasure too. THANK YOU, YOU REALLY ARE GREAT! From the much happier for finding your website student, Claire in London

ur chemistry site is wkd!!!!! Is this suitable 4 the OCR board double science or not? Cindy

Hi Doc Brown, Just wanted to let you know you website is a lifesaver. I'm a technician in a college and I'm getting dropped off the deep end with 5 hours teaching organic chemistry tomorrow due to staff absence!! I've done it all at degree level, but that was 12 years ago. I'm feeling a lot less scared now though, thanks for a great site! John


Hi, I just wanted to let you know I am very grateful I found you. Your website is better than I have ever seen and will make dramatic improvements in my SATs. (KS3) Shekar

I would like to tell you that (as you probably know already) your website is really useful and really organized. only doubt is if only I would have found it earlier instead of a month or so before the exams, thanks, Mohbin

Hi Phil, Thank you for your little message at the top of the Plants & Photosynthesis test. One of my year nine pupils pointed it out to me this morning just as we got started on the test; they were all very impressed! I believe 'The Head' (an ex-chemistry teacher so he can't be all bad) is going to mention it together with a plug for your website in his monthly newsletter to parents as I just happened to raise the subject over lunch. True fame at last my son! Kind regards, Richard

Excellent site, I use the word fills and revision checklists with GCSE pupils, with your logo on as acknowledgement. Hope this is OK. Thanks for all the hard work in producing an extremely useful resource. Simon, UK.

Hi, I'm currently studying for my GCSE's this summer, and just wanted to tell you how much your site is helping, thank you very much for the time and effort you must have put in. Tom

Hi Phil, as I mentioned to you in my email a month or so ago, I was planning to use some of your KS3 Biology tests for Saturday morning revision with parents and girls at Belle Vue Girls' School here in Bradford. Last Saturday was our big revision day and now I am writing to say a big thank you for allowing me to do so and also to report to you that your site was very well received by students but even better with parents. Most of them said that they really felt that the way the questions are structured has helped them to see which parts of the topic they need to brush up on. The head was also present and she appreciated the amount of work that has been put into the site.  Hope all is well with you and the workload is a bit thinner. As regards the school? It is an open entry comprehensive school for girls with over 90% Muslim students. Numbers are on the rise and we have over 1000 girls on role. I think (but don't hold me for this one ) that we were on the 16th place for improved schools and value added in UK this year. That tells a lot!! Hope this helps. Vlad (now retired the work-load is thinner!, I work most mornings on the website, but its the slower pace and feeling in control of the situation that makes the work more satisfying and hopefully, gradually improving the quality of the website to what it should be!!!)

Dear Doc Brown, I think your website is fantastic! I am working with a Year 9 class in an inner city comprehensive school. The class are a set 2, so some of the pupils are managing Level 5 of, more rarely,6, but the majority are around level 4. The quizzes are spot on for reinforcement and revision. However, I wonder if you could make it easier to print the quizzes, as I think they are good for homeworks, or lesson starters and it is not always convenient to use the laptops in class ( and not all pupils are on line at home). I have printed out several, but they are not particularly” printer friendly”. Any suggestions? Regards. Anna (print out the quizzes in landscape, but you don't get many on a page!)

I am so grateful for all the hard work you have put into this website, I am now directing all of my students to use your quizzes to help them revise. It is also very useful for student teachers looking for stimulus material for their classes. thank-you, Kim

Hi there Doc Brown: I am a chemistry teacher in Australia and thought I would give you some feedback per your request. Just came across your site and think you have a wonderful ambition  to put everything together in one place. Just having a look  around .. what you have so far looks good - the time taken must be enormous. Marion

When I first started teaching back in 'the 60s' I was much taken by the idea of Teaching Machines. They were a new idea, simple and conceived before there was any hint we might have  machines called computers in our schools one day. We were told they may well do away with the need for teachers in classrooms! Hmmm, I don't think even computers will quite manage that but  if you had seen my year seven class yesterday revising their 'Forces and their Effects' module on Doc Brown's web site you might well have wondered if there was really a need for a teacher to be there. They were absolutely absorbed and really thrilled if they managed to get 100% right. Many thanks again. Richard

I just wanted to tell you that your website is a great help! Good job! bluemarble282

Dear Doc Brown, Your website is brilliant, I found you pages on calculations a life saver! I have my first AS chemistry exam tomorrow and was convinced I was going to fail as I hadn't quite understood what I was doing in most of the calculations or where the numbers come from. But now I do! Thank you so much! I think I will do fine now. Jen

Thank you ever so much for your quick reply and your very helpful information you clearly stated on your website...your knowledge seems extensive and never-ending and I would like to thank you again for all the help you've given me. Thank you again...and good luck for the future. With kind regards, Emily 

Dr Phil Brown, I'd jus' like to say what a wonderful website you have got. I have recommended it to all my friends and they say its very helpful. I am currently revising for my first examination module and your website has been a great help, and I'm sure I am not the only one who thinks it according to the number of visitors on the site. Thank you for taking the time to put all the information up onto the web to share with everyone. Yours Sincerely, Becky 

Dear Doc Brown, I am a teacher, doing as teachers do on Boxing Day marking and putting together some revision resources! I stumbled into your site - what a find. After doing a number of quizzes and generally familiarising myself with a small part of your excellent site I would like to make it the main stay of our school KS3 web revision. Following your suggestion I agree that pupil familiarisation with the icons is a key to the effective use of your resources. My intended web page, in word, is attached for your perusal and permission to use your links to specific topics would be greatly appreciated. In such a format it would dovetail with our teaching most effectively. Looking forward to hearing from you. Geoff (permission granted to construct link page to quizzes using my icons and source fully acknowledged, and I've adapted the page for use on this site)

I just wanted to say thank you for making your site with chemistry notes. I've found it extremely helpful and I believe I might have been driven insane without it, so thanks again!  Christine

Initially I rather frowned on your neat little illustrations that go with each question because I felt that they would confuse students trying to understand what the question was asking but they are so good as illustrations that I now feel it would be a great shame if they were removed. I think labelling them as 'Examples!' is a good idea and I tell my pupils that they are generally not directly involved in the question and that seems to solve the problem (if one ever existed anywhere but in my mind that is). I used your KS3 Chemistry combined quiz - 8E and 8F - today with a normally pretty disruptive group of year 8 children and was very impressed by the way in which most of them got down to work and became quite involved in the quiz. In order to focus their attention I always give my classes a table to fill in when doing one of your quizzes. When they have found the correct answer to a question they have to grade it as 'Hard', 'Fairly Hard' or 'Easy'. The objective is simply to get them to think about the question itself and not just about getting the right answer. Many thanks again for providing us all with a really useful resource for our teaching. Richard

Thanks for such a fantastic, user friendly and fun site....As a PGCE Sec student its just such a good source of info, it must of taken you hours and hours. so many thanks for taking the time to so it. Just one thing, please could you do the same thing for Physics!!! Well a girls gotta try. Thanks again. Sarah

Hey Doc Brown - thanks so much for the incredible site that you have created.! I use it so often and now my pupils are asking for work from your site. I am delighted to see the jumbled up sentences for pupils to sort out - this builds nicely upon the types of activities from the KS3 Intervention and Booster materials. If you can, then more of these will be helpful for the C./D/E GCSE pupils. Again thanks for the resources and interaction for pupils. Regards Sarah

Hi Doc Brown, Firstly I love the animations and my year 8 (UK) classes all love the quizzes from your website. I would like to ask your permission to carry out an on-line test with the class in the near future, so do I just ask you by e-mail?!? Or do I need to contact you more formally?? Your site is fantastic on all counts, chemistry, biology and physics, I really don't know how you do it!! But I am sure glad that you do!! Thanks again, Doc Roberts

Hello again! I contacted you a little earlier this week, to thank you for putting your site on the web. It really did help immensely in my revision for my Yr. 9 SAT Physics Mock. Well this is just to say a double thank-you, as I got my result on Friday, and I am pleased to say I got 95% and only lost one mark in the entire paper! Thanks once again-your site really did boost my confidence. Rhea (Wales)

Searching for a fun way for year 9 to revise for exams after Xmas, stumbled across your site, thought it looked familiar from a few years ago, and yes it was! Student teacher with me on first teaching practice is also hooked! Glad you're still working hard, is this what retirement is all about ? Best wishes, have a great Christmas, see you around sometime. Sarah

I just want to say what a useful site this is. I am 47 and haven't studied chemistry since school. I am trying to help my son with the quantitative part of his GCSE course and your site with the worked examples is invaluable. Many thanks, Sharon

Hi Doc, Love the site and understand the amount of time spent putting it together - excellent work, sir! I teach secondary science (all 3 to GCSE) in the Midlands and regularly use your site to 'refresh' my memory. I think the content you have covered so far is great, especially as you have covered a lot of the new QCA stuff. Your quick MCQ tests are great and ones I will be pushing with my pupils now we have converted fully to the way of QCA rule, sorry, schemes of work. Many thanks and kind regards, Matthew

Doc Brown, big yes to animations!! and this is a wonderful site. I'm a student teacher and this is the best site I have found so far. Thank you, Donna

I have no queries but what I want to say is that your website is truly inspirational. And I really like the notes especially those on organic chemistry which I find very easy to understand. I happen to be an Open University student doing 3 science-based courses. Thank you so much for your website. It is really helpful. Maria

Just to say a big thank you, you're a legend for setting up this site. Thanks! Just thought I'd let you know appreciation of myself and many others....Its fantastic. Any plans for more A2 things pre-exams in June 2005 btw? Thank you again, Melanie 

Dear Dr. Brown, Thank you for the information. The revision notes are very useful. I have another suggestion to make. The opening page of your site index is quite different to read and understand for a first time reader. It would be more helpful if you took the information from your site index and put it on several different pages. This, that I have suggested above is only an idea. Presently, I feel that the website is quite helpful and informative, but I have to spend a couple of hours trying to orientate through the masses of information. However, many of my friends and classmates, are not as patient as I am, and so therefore feel 'overwhelmed' by your site index, and thus are discouraged to look further and do not use the website. This, I feel is a shame, since your website is one of the REALLY INFORMATIVE websites. Yours, Eliza (bravo!, work on the 4th re-navigation revamp has started)

Dear Dr. Brown, I have just answered one of your emails. I work for BT in India. I am very pleased with your Web site and have referred it to my wife who in turn has referred it to her colleagues and students. I am sure millions of students round the world are benefited by the simplicity of your website and makes Chemistry fun and easy to learn. You have a happy family, going by your website. May God bless you and your family in all your efforts. Regards Daniel

I don't know if you are still contactable by this email address - u helped me  out with a load of chemistry I was stuck with about 6 months back, I got my results and I got a B in my A level chemistry, with an A in maths and a B in  ICT, so I got into my first choice uni which was bath to study chemistry. just thought I would let you know that all turned out well in the end, and  to thank you once again for all your help. Abby

I am just about to start my NQT year as a chemistry specialist and would like to say thanks for the help your site has given me over the last year. It has been great for refreshing my knowledge (it was a long time since I’d tackled some stuff I had to teach). I’m sure I will continue using it in the future, especially for testing with pupils on the interactive tests. The only bad comment I can make is that sometimes the site (especially indexes) are too fussy – too much info, colours etc on one page. It can make it a bit hard to focus. Other than that, it’s great! Thanks again, Jenny

Animations help to fix questions (and answers!) in students' memories. Also help to keep subject light when exams make everything rather strenuous, many thanks for your excellent work on this marvellous site! Regards Elizabeth

Dear Doc Brown, It has been a while since I looked at your website and I was delighted to see that you were branching out into Biology and Physics for KS3 pupils. Thanks very much - a site like yours is invaluable for those of us with limited computing skills who want to make lessons more interactive and interesting for pupils! I will try to check more often to see what else appears in the next few months. Yours sincerely, Jane, Science Co-ordinator

hi I think your site is brilliant! it has really helped me with my studies and homework, I will continue to use your website for further information. thanks again Jonathan.

Brilliant site. some of the biology diagrams used (e.g. Unit 7A quiz) are a bit 'busy' especially for lower ability pupils. I have added your site to my Favourites and intend to use it in the classroom to brighten things up - this will be far better than boring paper quizzes. Val

Hi Thank-you so much. Your notes are very good and once I got your e-mail I started using them. I am a US teacher. I graduated from the University of Georgia with a degree in Biology. I am teaching 3 science classes this fall and I am preparing as much as possible for the year. Your notes are very helpful in organizing the material. I am mixing things up a bit from the textbook outline. I really appreciate your timely response and generosity! May God Bless You. April

The site really is magnificent. It helped me a great deal in the solution of problems I came across while doing the topic of bonding and structure. Sidrah

Hi there, We love your site and the information that we can cover but is it possible to take away the flashing images because they are so distracting that we can’t concentrate on the text. Emily(c)doc bto quiz animations

Hi, My name is Daniel, I come from Peru South America. I'm having IGCSE's this year, and for chemistry I found out that this web page is quite cool, thanks for doing it, the animations lighten me up when I'm studying Well ... I've got to keep on studying, bye, Daniel(c)doc bto quiz animations

Personally, I think it's a great site. It's pretty hard to find a coherent chemistry site on the internet and a fantastic one with quizzes, animations (it's great use since it sticks to your mind better than written explanations) and sectioned and detailed tutorials is about as rare as tap-dancing owls. It helped me a LOT in my modular exams. Thanks! Rsri45(c)doc bto quiz animations

Hi Doc Brown! I am a 16 year old Singaporean girl who will be taking the GCE ‘O’ Level this year. I came across your site by accident earlier this year and has been using it ever since. It had been a great help and I just wanted to thank you for taking time out to put the Chemistry information online. Though I am not studying the exact same topics as the Western countries, I had received a lot of help from your site. Thank you once again and keep up the fantabulous (fantastic plus fabulous) work. Yours Sincerely, Abra Chan

I would like to say thank you for making such a brilliant site. Being so close to my modular sciences, I was dismayed to find my teacher had mislaid my book during her absence! Your site taught me all I needed to help me remember and I'm writing so say thank you in saving me from months of catch-up! Thanks a lot Cassie (we never lose books Cassie, we carefully store them and forget where put em'!)

Wow! Your web-site has been such a help, in gathering all my thoughts together in preparation for my exam tomorrow. It has also helped me extend the revision I was doing at home too. I am hoping to do Chemistry at Bath university next year, so I'm hoping to get an A in Chem, I’m sure your site has helped me immensely working towards this. Anyway, thanks for making a brilliant resource for everyone who’s doing chemistry, I have recommended it to all my Chem friends. Thanks James (I sincerely hope you get an A in chemistry and bon voyage to Bath)

To whom it may concern: I really like ur site and believe me it has helped me improve my organic chemistry (nomenclature) greatly. thanks a million for such a helpful site because most of the sites have tons of info whereas ur site has tests as well which are key to success. I would like to make a suggestion...could u make ur site a bit more organised because sometimes I work out the questions and then I can't find them again since all ur tests are please make available the answers to all ur tests separately...if u could do that I'd be very grateful...and what's more ur site be da best ever still is!! Regards, Maleeha (the navigation is slowly getting better, I hope?)

I am a biochemist, and I was searching the net for some information and came across your site, Doc I feel that it is a very informative site for young up coming chemists, keep up the good work. Craig

Hi there, I'm an ex Head of Chemistry from Ripley, Derbyshire with some 25 years teaching experience. I'm now in a place called Takaka in Golden Bay at the top of the south island in NZ with my family teaching.. you guessed it...chemistry in our small school. I'd just like to say a big thank you to a fantastic on line resource and a source of inspiration. Like you I still love teaching and our attempt at a lifestyle change has been a real adventure. I can let you know about the NZ system of achievement standards if you wish. In the meantime carry on the good work and once again a great big thank you. Paul

Thank you very much for this site it has been a great help over the past 2 years. Yours, Laura

I am trying to develop my own chemistry website for our school but I do not have many ideas at the mo! Would you mind if to start with most of the pages had links to your site. It means that my pupils can access your excellent content easier. Samantha, teacher (no problem!)

Dear Doc Brown A most excellent site! I have been using it for well over a year now, having stumbled across it via "Google" one day. It is by far the best online resource for GCSE chemistry and consequently I strongly advise my students to make use of it. I have even informed them to use it for homework, ahem.. I have taken the liberty of building a link to your site from my own. I hope this is ok! Best Regards, Bryn

Hi, we were doing tests on the site as part of our revision in class, we have the head of science for inorganic and he loves your site. I must admit it is very useful. all the information is there in front saves us wasting time trying to find. Some of the revision books are useful not all the information is as accurate or as easy explained as on the site. Must have taken a long time to make all the tests with the programming and then publishing it on the web. I know what a pain html can be. Thanks for replying so quick and updating everything. we have been on study leave so this is the first time I have had chance to check my emails. The exams went well yesterday, chem for life was must easier than the chem for natural resources, although I should imagine I have done pretty well. anyway, back to revising for philosophy. Ashley, Salters student

Thanks. And by the way, your website is REALLY cool. It has helped a lot. Dan

I have found your website very helpful with my studying for my Gcse's examinations so thank you for all your help. Although your website is fantastic I have found a piece of incorrect information that I would like to bring to your attention. In one of your Earth materials multiple choice higher tier tests there was a incorrect answer. The question was number 7. It is which three numbers a, b and c are required to balance the equation a Na (s) + b Cl2 (g) = c NaCl (g)? [13] answer a which is the same as answer b was 212 which is correct was marked as incorrect whereas the same answer in b was marked as correct. they are both correct but only one of the answers was written as correct. I'm sorry but I thought I would bring this to your attention. it is only a small mistake among such wonderful work. yours faithfully Alexandra (no need to apologise, thanks, corrected and uploaded in 10 minutes flat!)

Hey Doc Brown! ur website is great! there is no way I would have been able 2 pass my chemistry degree without u! thank u for all your help. how can I repay you?! I am now a midwife and chemistry is very important 2 me. Can I repay u by delivering ur babies! Thanks Again, Dr. Abholgefilius ( a likely story!, GCSE in mid-wifery!)

Hi, Thanx for the brilliant website you have. I am so grateful for your hard work. Is it possible for you to tell me of any biology and physics websites as good as these to revise for the year 10 GCSE modular exam 2 and 9? thanks Danya

What a fantastic site! I am currently in year 13 and studying Salters chemistry in a school in south Wales! Without your site revision would have been a nightmare, picking out all the important bits! You have saved me hours of work and you need to be applauded!!! There really should be a reference to your site in the storylines/chemical Ideas! Thank you so much! Vicki x

To whom this may concern I think your website is the best for any help anyone could need for chemistry I like the new idea of the exam bashing thoughts. There is one thing I think you should add in your website to make it complete is past exam question which will make it a lot easy to revise. thanking you in advance your Sareena (can't help on past papers, breach of copyright law I'm afraid!)

As I prepare my lessons in advance, the site is good it has enough visual and interactive stuff for the weaker students and also the full GCSE Chem syllabus for the more 'academic' chemist, thanks!!!!! teacher Ruth

Dear Doc Brown, I have been using your site for a few months now, and have finally got round to emailing you to say how absolutely fantastic it is. I am actually a post-doc in molecular biology and biochemistry at university, but I have started doing some private tuition in my spare time, to both a GCSE and A Level chemistry student so your site is very useful to me. (More A Level stuff would be greatly appreciated when you get time !!!!!) I am also thinking about going into teaching full-time, as I am getting to that too old-too and expensive-too specialised time in my career (and at only 32yo) which means getting the next contract is going to be awfully difficult (expiry October). Any advice would be appreciated ! I am particularly interest in colleges of FE teaching A level HND etc. chemistry/applied science but having no luck so far. Once again, many thanks and keep up the good work. David, teacher (good luck, but you must do a PGCE course asap)

Hi thanks a lot for the information. Today we had to do our presentation and the teacher loved it. I would like to thank you once again for your help. It turned out to be great and we even did the experiment you had told me about. Thanks Charlotte (Malta) 

Hi Doc B, sorry for replying this email hasn't been working for a couple of days....anyway thanks for all your was much appreciated.... we've all completed the titrations now (thank god!!!) and our teacher did come back and she also said that we wont get penalised for having it the other way long as we explain each step. Well anyway thanks for the help. Oh by the way your site is still ace for help on chem....u dun a gr8 job! Shaima

Your site was more helpful than any other one on Google. Roy (Doing GCSE science in England)

Hi, I am a regular visitor to your web site. Thanks for putting up good contents and useful notes for teachers. I wondered if you could kindly forward me Triple Science Physics Syllabus for GCSE. Many Thanks Renu Joshi (no time for the physics I'm afraid!)

Hi your website is really cool. At school we use it during our chemistry lessons. Thanks for making chemistry seem fun and enjoyable. C. Bajada

Just like to say great job on the website, you must of put a lot of time on it. Richard

Thank for your website. I teach children with difficult backgrounds who do not have access to many books, or much colour in their lives. Your website has helped me inspire them to want to understand and pass their GCSE. Teresa

Dear Doc Brown, Your chemistry modules have been a life saver. Schools these days don't employ genuine chemistry teachers and can't afford the books. My daughter is using your site to revise for her science GCSEs and it's proving invaluable. I appreciate all the hard work you've obviously put into it. Regards, a grateful dad

Dear Doc brown! I just wanted to congratulate you on your wonderful web site! I am absolutely inspired by the work you have done! I have just come back to teaching science after a few years out and was trawling the net for some good ideas and support and found your site! I have found lots of helpful ideas already! MANY MANY THANKS. I think you are "retired" but hope you are able to continue with some of your wonderful work! Patricia ( Brussels)

Dear Doc Brown, I am currently in my NQT year teaching at a secondary school in Norfolk. I would just like to say that it's refreshing to find such a brilliant website that is aimed at the English National Curriculum. Also I was wondering if you have any tips for teaching the Salter's AS  Chemistry. I started teaching the course in September and I find it quite difficult to know which areas the students would need most help on. I would greatly appreciate any words of wisdom you could offer. Thanks for the great website, I will make sure my pupils find out about it. Lucy (words of wisdom - dangerous Q!)

Hi there! I do link lots to your site, cos your quizzes are great for lessons in the IT room - the kids love them. Only problem I have with your site is navigation, I find it a bit hard to find my way around. I reckon you could fix that with one summary type page, listing all the major topics by  year/key stage. By the way, have you seen the latest version of Hot Potatoes? Version 6? It's fabulous. Thanks for contacting me, your site is really great. My deputy head wants to extend my project to cover more areas of the school too. Kat (redoing main index page to improve navigation, agree on HP software, BUT have to watch HP6, it won't work on some earlier browsers and operating systems)

Hello there, I discovered your site almost a year ago now and am pleased to say I am currently studying AS Chemistry at Oxted School, Surrey. I would like to say a very big thank you for all the hard work that you have put in, it is seeing myself and my peers through our AS course. The tests are excellent for revision, and the exam bashing thoughts are superb too. Our chemistry department is in debt to you, and so am I. Thanks for your continued hard work even into retirement! Tom

Thank you for the answers. This site is the best I have found for Chemistry, I am an NQT and am so grateful for the resources. Elisabeth.

Hello! This is Ricky. I sent you an email a few weeks ago. You told me give  you some feedbacks of positive and negative. I have been thinking of them for a long time. I have concluded them as the followings. Positive: Detailed analysis of the syllabus with extra points. ( I use that all the time). The exam bashing thoughts are excellent! Analysing every single concept in CS, CI and also the activity sheets. The backup materials for me to practice and test myself. (I use it when I don't feel confident about naming compounds.) Some detailed explanations of some hard topics. (such as the proteins in EP). Negative: The EP page you scanned is very hard to read. If you are too busy to type in. You can send the scanned picture to me and I  will type it for you. I am so happy to do it as your website helps EXTREMELY  a lot! And I think I must help you in order to say thanks. Syllabus numbers. In the Salters syllabus, it uses alphabets. But, you use numbers.( I need to check whether my syllabus is exactly the same as yours to prevent missed leaning.) So, it is very hard for me to check. In the syllabus, there is some words in BOLD prints. But, I don't know what they mean. (I will send to you much more positive and negative points when I find out) Also, could I ask apart from (the website SAC provide), whether you have any other websites for A2 coursework. Thank you very much! Ricky

Hello I am a first year degree student. This was the first time I used your site and all I can say is fantastic!!!!!!! Something that seemed impossible to do turned out to be very easy thank you!!! Jenna

Hello sir. My name is Xain and I am a big fan and a regular visitor of your site. Before coming across your site chemistry was nothing less than a nightmare to me. But things started going well once I fortunately found your site.

I think the website is excellent but with the calculations (deducing empirical and molecular formula) it would be good to show the workings of the equation so you could see where you have gone wrong. Apart from that the website has been a fantastic help, really good! Julie (the working will be included eventually!)

Absolutely delighted to find this site by chance. Have just taken on 6 weeks of supply teaching and am jumping in with both feet to return to A level Chemistry after a 16 year break. Hoping to swim not sink! Wonderful help here. Thanks a lot Dr Brown. Diane (bon voyage on re-flotation!)

Just had my chemistry test today and felt pretty confident about it. your site helped a great deal and I would really appreciate it I'll let you know when though. Thanks very much again Doc I'll definitely recommend your site to my fellow struggling chemists god knows there are plenty of us out there! Andrew, AS Salters student

just writing to thank you very much for creating this web page, it has helped me a lot in my revision! I now feel a lot more confident and happy about taking my exams this month. Lois

Hello! I am Ricky who is currently a Yr-13 student. I am currently studying Salters Chemistry A-level. Your website is extremely useful and very professional! Unfortunately, I have noticed your website a week ago. But, this website gave me lots of help for the module 2851. 

Just writing to thank you very much for creating this web page, it has helped me a lot in my revision!  I now feel a lot more confident and happy about taking my exams this month. Lois

I am a Chemistry Teacher at Qatar, and have recommended your fantastic site for Chemistry revision to my year 11 class- they love solving the crossword puzzles! Thank you! Dr Shaikh

hi there....... WOW.. this site is awesome.......... too good.. this is a complete revision.. plan... nothings missing.. just wanted to ask u that ... if u could gimme some studying tips.. I'm in KS4 O levels GCSE can u tell me some planned timetable.. I can stick to.....  a little bit weak in chem.. can u tell me how do I gain my interest in it? Usman

Hi my names Will and I've been using your website for GCSE chemistry trying to get my (difficult) coursework done. In school our teacher gives you much praise for your hard worked site, and recommends highly for us to use it. I was wondering if, by any chance it would be possible to put his name on the site somewhere and for you to say hi to him, it would make my chemistry class year! Thanks for making the site anyways, and its helped a lot with all the work.  Hey its me again, if you can put my teachers name somewhere, his name is Mr McLoughlin

Doc, Thank you for creating such a wonderful web site!  I realize it is intended for students and teachers, but it has been an invaluable resource to me.  It is put together well, and I commend you for the great wealth of information that is available. I would like to ask you about some chemical reactions ..... Lynn (Nasa!)

Dear DOC I've just discovered your website and I am really blown away by what you have done. As teacher of 11-16 year olds in Surrey I am very aware of how much time and effort has gone into this. I am planning on recommending your website to my students this year. I hope it and you continue to flourish. Good luck in your 'retirement' Regards, Chris (retirement is going just great!)

I am just writing to say that I have been looking for a good modular GCSE science revision site for so long, and then I finally found yours and it is fantastic, really helpful. I liked the multi-choice tests as you can just click repeat test and it brings up a different set of questions so you can really find out what you are weak on and cover everything. I also enjoyed the poetry part as a bit of light relief Thank you so much again, Louise

Fantastic website! I teach science at an Enfield school. I found your website very informative and the pupils in several of my classes thoroughly enjoyed the internet based lesson using your website to consolidate learning. Probably the best educational website available on the internet. You have restored my faith in internet learning. Samantha 

Doc Brown, What a generous and inspirational site you have.  Thanks for your generosity! Peace, Kimberly

This site has helped no end in my struggle to cram into my head all the information I needed for my science access course,  A brilliant site ! Thanks, Jo

What a fantastic and wonderful site. A big Thank You from parents all over the world. Solinder

how hard is it to run a website like this when you are so old? piggy (not too bad when you are retired!)

Doc Brown - I just wanted to say thank you for your brilliant revision site! I used to revise for my GCSE's, and I got 2 A*s. I'm planning to use it for AS too, can you guarantee me as good results?! thank you, Katharine

Hello! Yes I am studying Salters A2 SS, thank you very much for all your help, it is just what I needed :) Much appreciated! (lifesaver!!) Regards, Emma

Hi! Having just finished a year on the graduate teacher training programme and now embarking an a career as a chemistry teacher, I LOVE YOUR SITE!  What's more the kids think it's great too! (Far nicer than piles of revision books!). I would like to see links to the subjects required for the C of EA syllabus as well, as these pupils are those who are often scared off by the 'big words' when we are trying to navigate through the more complex KS4 work. On the whole, as I currently teach single, double and triple GCSE science (Chem) as well as C of EA, keep up the good work and keep the site expanding!! Cheers, Leila

Hi Doc Brown, Two weeks ago I received my AS level results and I got a grade A in Chemistry. I am positive that without the increase levels of confidence that your site gave me this would not have been possible. I went from dreading calculation questions to considering them as fairly easy marks. I will recommend your site to my younger friends. Thanks very much again and keep up the good work. Luke

Hi, am just writing to say that I have been looking for a good modular GCSE science revision site for so long, and then I finally found yours and it is fantastic, really helpful. I liked the multi-choice tests as you can just click repeat test and it brings up a different set of questions so you can really find out what you are weak on and cover everything. I also enjoyed the poetry part as a bit of light relief. I've recommended your site to some of my own teaching buddies and they reckon it's "pretty cool" and "a great resource", so there you go... You will definitely be remembered for putting together such a comprehensive site! Thank you so much again, Louise (via searching for much loved ex-teacher Kathryn Williams)

Dear Doc Brown, As a busy science teacher I have spent 2 days on the web finding resources and researching the quality of resources on the web. I have hit your site many times and felt compelled to write to say a huge thanks for such innovative ideas and resources. What a lot of time and expertise you have put into the site and it is a joy to read both in terms for the pupils and teachers. Thank you. Sarah

It is a bit hard to understand how the web site work, because it does not go in to detail about what you are going on to until you are on it. It would be good if when highlighting the chosen question a drop down box would appear and tell you what it is containing? But other wise the web site is really useful. Chris

this site is crap, there are no games on it ???? (tough!, do get any games on exam papers?)

Just a quick note to say that I had my last Chemistry exam [and my last A2 Exam...!!] this morning and on the whole, it seemed OK (I hope), but of course you can never be sure.....! Thanks very much for all your help over what must be almost the 2 whole A-level years now! Happy retirement - sounds like you deserve it! James

WOOOOOO THIS SITE ROCKS ???? (bound to if you stated learning chemistry in the 60's!)

your websites really good but the site that u have made is excellent but v. hard to navigate the installation of a search bar wouldn't go a miss!! keep up the good work doc Shailen

Well, I am taking "Introduction to Chemistry" at Santa Monica College (a mile from the beach -West Los Angeles) which is a Community College or Junior College.  I found your website by doing a search for C2F2 and chemistry. I'm glad to be the first question from L.A. I found your website very interesting and enjoyed the pictures! We are learning to name molecules and ions from the written names, and name them from their formulas. Thanks again. Giovanna

Well, guess that's it then ? Thanks for all your help, u've been brilliant, Exam wasn't too bad (touch wood!!), Emily

One of my students directed me to your website, which is brilliant- well done! Just a couple of comments though: In the test on EL, you have an unbalanced equation which you are giving as a correct answer M(OH)2 H2SO4 > MSO4 H2O Also, in the test on shapes of molecules, questions 7 and 10 will accept "bent", but not "v-shaped". Keep up the good work. How do you find the time? Best wishes Anne

The name is Gordon Gentry (a really cheesy email address but it keeps my students amused!). I am a Head of Science in Herts and work for Homework High at Channel 4. Your site is one that we often send students to for help when we can't do the business!

Your excellent website was recommended to me by a consultant to the Royal Society of Chemistry, so I have put in a link in the "Interesting websites" section of my website: Australia ????

Hey, just wanted to say that your site is great and is very useful! one thing though, I have my science modules tomorrow, you have revision for module 2, maintenance of life, but not for module 1, humans as organisms, or then I just cant find it, please can you e-mail me back on ?? and tell me please. Thank you! Farihah

I am currently revising to do my A2 Chemistry Salters exam and I am just emailing to thank you for the time and effort you have put into your web site. I have printed out the breakdowns of the syllabus and the references for the chemical ideas and storyline pages and used this as a tick list while going through my revision process. Before I found this web site I didn't know where to start! Thank you again for making this time easier for me. If only u had designed websites for my other subjects. Keeda

THANK YOU  I am incredibly grateful for the hard work you've put into this website as it has helped me and my revision infinitely! Ruth

Just wanted to say thank you for having such a good website for A-level chemistry. If I hadn't found this on the net I don't know how id have organised my revision, I've passed on the address to my chemistry teacher and she loves the site too. I've very very nervous about my chemistry re-sit tomorrow and the synoptic next Tuesday, but your "exam-bashing" pages are SO good. If I get a good grade I think I'll owe it to your website! Thank you :) Keep up the good work. Jemma

Hi again Doc, The AS year is almost over now and can I take the opportunity to thank you for your website which has been a great help to me over the time.  Kind regards Brendan

I am a student studying the Salters chemistry course at ... and I'm writing to thank you for the invaluable help your revision site has been. It has given us all so much more time for revision rather then plodding through textbook's and in particular your 'exam bashing thoughts' were a really good idea. Have a nice retirement and thank you very much for your help. Sarah 2

Thank you the information you gave me was amazing thank you so much!! ???

Just a quick e-mail to say what a great site it is. I looked through a chemistry sample paper and didn't understand deducing empirical formulas properly. However, with the help of your excellent website it has all become clear. Thanks a lot!  ???

Thank you so much - it is for my daughter and she is very appreciative. Barbara

I found ur website last night at about 12:00pm (03/06/03), my chem xam 4 da same course u cover (Salters) was at 9:00 (04/06/03), it was by chance I came on the net at that time, I was reading thru my notes n found I was, contradicting myself on octane rating on one page I said how a high octane rating caused lots of knocking and on another page how high octane rating caused little knocking when I came across ur site I was like oh My God this is da best chemistry site I have ever seen u have duna gr8 job n explained everything really well n ur tests ourselves r really excellent that helped me a lot on naming things which did cum up on the AS xam yesterday things u might wanan add onto ur site are 1. sum actual xam questions 4rm the OCR board and the words that they like to have in certain answers e.g. in photo dissociation molecules get EXCITED 2. a bit more on the storyline neway thank you so much for a gr8 site it really helped me pass my xam Ryan

I am an NQT teaching GCSE and Salters’ AS level Chemistry and I’d like to thank you for your web site and all the support it’s given me through this stressful year. Whenever I’ve been unsure of a section in the AS level specification you’ve had the notes to help me along. In terms of lesson planning and preparing revision sessions your site was a God-send. I have also recommended it to my students to use it to clarify any topic they are unsure of. Also, due to unforeseen circumstances I was forced to condense the Atmosphere Module into just 4 weeks of double lessons and your site provided overviews of all the Salters’ Sheets so I could easily decide which were the most important practicals and worksheets to focus on.  I hope when I have gained as much experience as you obviously have, I can be as supportive to students (and new colleagues!) as you have been.  Thanks again. Hannah

thank you for your help, your site helped me a lot in terms of revision, and I will be using it frequently for my A2 course next year and thank for your time kiran


Thanks very much, this site has taken me from being nervous with calculations to feeling very confident.  I am doing my AS levels and you have given me the confidence I need to do well. Thanks again, Luke

One of the questions in this section is incorrect. It refers to the bond energy of N-H being 1664/3 = 338!!?? I think the 1664 has crept in from the methane data question. Fantastic site by the way. I recommend to all my students. Keep up the good work! ???

What a great website, well done. Stephen

Hi I am Hilma. Brilliant website. Found it very useful Thanks. I am looking for igcse biology websites. Can u help me.

Mum liked the website. I found the site really friendly to use and I thought the quizzes and the Cloze procedures were very good. I used the site on Friday and I recommended it to several schools during the day so you should have had a big increase in the number of hits! I'll keep monitoring the site for any new material, would you like to do the same for physics and biology? It would be a wonderful resource! Thanks again, Josh

Brilliant! Hello there! Just thought I would drop you a line to say how useful I have found your site. I am most impressed with the information, tests etc you have included and I have to say that your site is going to make my life very easy indeed. In fact, I am hoping to put links from our college intranet to your site [providing you have no objections!] Thank you very much, from a grateful [and now feeling ever so slightly  inadequate] chemistry colleague. Nikki

Your web site is Great ...... the science teacher had to keep cheating!!!!!!!!! thanks, Owen

Thanks for the info of the web site its really good and helpful. Victoria

I have emailed you tell you how wonderful your website is. I've moved school as part of my PGCE and have changed Syllabus as well. I have told everyone about your web pages...I think they are great. Please continue with your work! Sadia.

The exam bashing thoughts are really useful in having an overview of the unit and a brief intro of each section. I also like your tips on the exam itself - very handy (I'll print it off) but I was surprised by some of it e.g. past papers not being the best thing to do as I usually find them quite helpful for my other courses. Andy

Brilliant site! But Q51 (energy) of test gives wrong answer, I think. Dave

Doc! You're are seriously the nuts!! Thanx so much for producing such a wicked Chemistry page, u have no idea how much it has helped me (and no doubt a few thousand others!)! Hoj

I really enjoyed your site. I think it is very useful and can see many applications of it both in school and for the kids at home. We are currently a member of staff down at my  school and I am considering using your site for pupils who will need work set for their 'non-science teacher' lessons. I think it has a big future and will happily recommend it to my Science Department colleagues. THANKS Sarah 3

I am most grateful for your kind, gracious reply to an information request from my student Menatallah aly from Egypt . You have motivated her, and actually all of my AS & O level students (about 65 in all). I can not thank you enough. Dr Mamoud, Cairo

It is THE best site I have ever been on because of the multiple choice questions and revision notes. I just HAD to say it!!! Thank you VERY much ????

I hope that I am not a load on your mail box . but I '''ve just wanted to tell you thanks about the last mail, you have really nice family! . I ''ve shown my friends all the pictures and they were surprised that a big doctor like you would reply for a message from a small student like me! hoping that you would accept me as one of your foreign friends and I will send you my picture later. say hi to the family. yours, Mennatallah

Dear Doc B, I am currently in the 10th grade. I am taking honours chemistry and we just got our element tests back. I got a hundred, thanks to all the practice I got from your quizzes. Thanks again! Parakeet333

I teach grade 9 and 10 Sc in Sudbury ON Canada. I LOVE your chemistry site and wonder if there also are physics (motion, acceleration, velocity, displacement) info with similar set up than Chem! Electricity, weather are also other topics of interest! What a fantastic site! Keep up the good work! Lisette

Hi great web site it is really helping me do the revision for the mocks on Thursday. I will be in your classers next year and at the open evening I was really impressed with what the course involves. Adam

I am Asad. I am a student of gcse. I like this website and really appreciate your efforts. You have been marvellous in doing such a wonderful job. I need your help in preparing for my test. I have a test on acid bases and salts. Bye Asad

I am really thankful for the CHEM IGCSE website you have made.. I am sure it will help me when it is time for my exams.. I am going to do my IGCSEs this year..  but I wonder if you have another website for other subjects like biology or physics and maths.. if you do .. please can you send me the websites.. ? if you don't .. do you know other websites which offer them ??? thank you again .. Mai - Bahrain

Just to say thanks for helping one of my students. Hannah got a c which was as a result of extreme hard work. Thank you once again Dave

hello. Its been a while since I've had the chance to email you. well results have come and gone and well lets just say for the rest of my life I'm in yr debt! I cant believe I did so well and its all yr revision sheets and extra help. Hannah

Just a word of appreciation. Struggling with reversible reactions with my son, I came across your site through Google. We've struggled through text books, standard websites and yours is the best for clear explanation. We have yet to try the assessments. Laura

I think your website is brilliant, and has really helped my study of chemistry to A level. However, one thing that I always fall down in in exams is the experimental side, and I know this is also true of a number of colleagues who also use this website to aid revision. Although the Salters Activities show the different chemical techniques, e.g. heating under reflux, what would be really useful would be a simple explanation of each process, and examples of what each process is used for. I do not know how practical this is, or if you know of any other place where we could find this information, but any advice would be much appreciated. Allyson

I wanted to tell you thank you so much for the information you sent. It helped a lot and it encouraged us to get started much sooner. Anyway, it is our annual science fair at .... and the kids get different subjects to pick and that was the one my son selected. Thanks, Kamelia

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