Doc Brown's Chemistry Unofficial Support for
Zimbabwe O
level chemistry syllabus 5071 specification
ZIMBABWE GENERAL CERTIFICATE OF EDUCATION (ZGCE)
ZIMBABWE SCHOOL EXAMINATIONS COUNCIL
(ZIMSEC O level chemistry examinations in November
2013-2017)
general [useful
O Level chemistry revision notes]
index
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1 THE PARTICULATE
NATURE OF MATTER (physical states of
matter Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the states of matter and explain their inter-conversion
in terms of the kinetic particle theory;
(b) describe evidence for the movements of particles in gases and
liquids (the treatment of Brownian motion is not required);
(c) describe and explain diffusion;
(d) describe the dependence of rate of diffusion on molecular mass
(treated qualitatively).
States of Matter
- particle theory - gas, liquid & solid properties-behaviour, state
changes
2 EXPERIMENTAL TECHNIQUES
(laboratory procedures Zimbabwe O
Level Chemistry 5071)
2.1. Apparatus
(laboratory equipment Zimbabwe O
Level Chemistry 5071)

You
should be able to:
(a) name appropriate apparatus for the measurement of time,
temperature, mass and volume, including burettes, pipettes and
measuring cylinders;
(b) design arrangement of apparatus, given information about the
substances involved;
(c) describe the use of volumetric apparatus and indicators
including methyl orange and screened methyl orange;
How to
do titrations and calculations e.g. acid-alkali titrations
(and diagrams of apparatus)
Dilution of solutions,
apparatus
2.2. (a) Criteria of purity
(importance of testing for purity,
chromatography Zimbabwe O Level Chemistry 5071)
You
should be able to:
(i) describe paper chromatography and interpret chromatograms
including comparison with ‘known’ samples and Rf values;
(ii) describe how chromatography techniques be applied to colourless
substances (knowledge of the composition of particular locating
agents is not required);
(iii) identify substances and test their purity by melting point and
boiling point determination and by paper chromatography;
(iv) explain the importance of purity in substances in everyday
life, e.g. in foodstuffs and drugs;
Definitions and
criteria in chemistry
eg atom, molecule, formula, element, compound, mixture, pure, impure etc.
Paper
& thin layer chromatography (tlc)
2.2. (b) Methods of purification
(how can we purify materials?
Zimbabwe O Level Chemistry 5071)
You
should be able to:
(i) describe methods of purification by the use of a suitable
solvent, filtration, crystallisation, distillation (including use of
fractionating column) (refer to the fractional distillation of :
crude oil, liquid air, fermented liquor);
(ii) suggest suitable purification techniques, given information
about the substances involved.
Distillation - Simple and
Fractional
Distillation
Filtration, evaporation,
crystallisation, drying
and
decantation
3 ATOMS, ELEMENTS AND COMPOUNDS
(Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) state the relative charges and approximate relative masses o
protons, neutrons and electrons;
(b) define proton (atomic) number and nucleon (mass) number;
(c) use and interpret such symbols as ;
(d) use proton number and the simple structure of atoms to explain
the Periodic Table, with special references to the elements of
proton number 1 to 20;
(e) define isotopes;
(f) state that some isotopes are radioactive;
(g) describe one medical, and one industrial, use of a radioactive
isotope;
(h)
describe the build-up of electrons in ‘shells’ and understand the
significance of valency electrons and the noble gas electronic
structures.
(The ideas of the
distribution of electrons in s and p orbitals and in d block
elements are not required)
(Note
that a copy of the Periodic Table will be available in the
examination in Paper 1 and Paper 2).
Atomic Structure
- nucleus, electrons, isotopes etc.
Periodic Table Notes -
section on electron structure
3.1. Bonding: the structure of
matter (Zimbabwe O Level
Chemistry 5071)
You
should be able to:
(a) describe the differences between elements, compounds and
mixtures and between metals and non-metals;
(b)
describe alloys, such as brass, as mixture of a metal with other
elements
Definitions and
criteria in chemistry
eg atom, molecule, formula, element, compound, mixture
Periodic Table Notes -
an overview - section on comparing metals & non-metals
3.2. (a) Ions and ionic bonds
(Zimbabwe O Level Chemistry 5071)
You
should be able to:
 
(i) describe the formation of ions by electrons loss or grain
(ii) describe the formations of ionic bonds between metallic and
non-metallic elements, e.g. in NaCl, CaCl2;
(iii) describe the lattice structure of sodium chloride
(iv) describe some ionic compounds as refractory materials, e.g. MgO
as a lining in furnaces.
Introduction to Chemical Bonding
Ionic
bonding and ionic compounds and their properties
3.2.
(b) Molecule and covalent bonds
(Zimbabwe O Level Chemistry 5071)
(i) Be able to describe the
formation of covalent bonds between non-metallic elements leading to
the noble gas configuration, e.g. H2, Cl2, N2,
HCl, H2O, CH4, C2H4,
CO2 ??? it said C4H4CO2 on syllabus - printing error?
(ii) be able to deduce the electron arrangement in other covalent
molecules;
(iii)
be able to construct ‘dot and cross’ diagrams to show the valency
electrons in covalent molecules
Introduction to Chemical Bonding
Covalent
bonding and small molecules and their properties
3.2. (c) Macromolecules
(Zimbabwe O Level Chemistry 5071)
(i)
Be able to describe the structure of macromolecules such as
graphite, diamond, silica (SiO2, silicon (IV) oxide,
silicon dioxide) and poly(ethene)
(ii) Be able to describe the similarity in structure of diamond and
silicon, diamond and silica (silicon (IV) oxide) and of their
properties related to their structures.
Introduction to Chemical Bonding
Covalent
bonding and giant structures and
their properties and uses
Addition polymer
structure - properties and uses including poly(ethene)
3.2.
(d) Metallic bonding (Zimbabwe
O Level Chemistry 5071)
You
should be able to describe metallic bonding as a lattice of positive
ions in a ‘sea of electrons’ and explain the electrical conductivity
and malleability of metals.
Introduction to Chemical Bonding
3.2. (e) Physical Properties
(Zimbabwe O Level Chemistry 5071)
You
should be able to relate the volatility, solubility and electrical
conductivity of a compound to its structure to its structure and
bonding.
These ideas are covered in the individual
sections above.
4
STOICHIOMETRY AND THE MOLE CONCEPT
(Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) state the symbols of the elements and formulae of the
compounds mentioned in the syllabus.
Element symbol & name QUIZ
- easier-pictorial
or Element symbol &
name QUIZ harder - no
pictures!
Quiz on the naming
and formula of chemical
compounds
(b) deduce the formula of a simple compound from the
relative numbers of atoms present and vice versa;
(c) determine the formula of
a ionic compound from the charges on the ions present and vice
versa;
(d) construct equations with state symbols, including ionic
equations;
(e) deduce the balanced chemical equation for a chemical reaction,
given relevant information;
Multiple Choice
Quiz on balancing Symbol Chemical Equations
with numbers
Number fill Quiz on completing symbol equations (Q1
Q2
Q3)
How to write
word & balance symbol equations, work out formula and name compounds
(f) define relative atomic mass, Ar;
(g) define relative molecular mass, Mr, and calculate it as
the sum of relative atomic masses;
What is
relative atomic mass? (Ar) and calculating relative atomic mass
Relative atomic mass - type in answer
QUIZ and
Relative atomic mass - multiple choice
QUIZ
Calculating relative formula/molecular mass (Mr) of a compound or element molecule
Type in answer quiz on
relative formula mass and
Multiple Choice quiz on
relative formula mass
(h)
use the mole concept to calculate empirical formulae and molecular formulae;
Introducing moles: The connection between moles, mass and formula mass
Introduction to moles type in
answer QUIZ and
Introduction to moles multiple
choice QUIZ
Using
moles to calculate empirical formula and deduce molecular formula of a compound/molecule
(starting with reacting masses or % composition)
Empirical formula type in
answer QUIZ using moles and
Empirical formula multiple choice QUIZ using moles
(i) calculate stoichiometric reacting masses and volumes of gasses and
solutions, solution concentration being expressed in g/dm3 and/or in
mol/dm3; calculations involving the idea of limiting reactants may be
set.
(Questions
on the gas law and the conversion of gaseous volumes to
different temperatures and pressures will not be set)
Reacting mass ratio
calculations of reactants and products from equations
Type in answer QUIZ on
reacting masses and
Multiple choice QUIZ on
reacting masses
Reacting gas volume ratios (ratio of gaseous
reactants-products)
Reacting volumes type in answer
QUIZ and
Reacting volumes multiple choice
QUIZ
Molarity, volumes and solution
concentrations (and diagrams of apparatus)
Molarity type in answer QUIZ and
Molarity multiple choice QUIZ
(j) Calculate % yield and %
purity
% purity of a product
% reaction yield and theoretical yield calculations,
why never 100%
How
much of a reactant is needed? calculation of quantities required, limiting
quantities
5 ELECTRICITY
AND CHEMISTRY
(Zimbabwe O Level Chemistry 5071)
Electrochemistry
Notes
- an introduction to electrolysis, theory, electrolysis cells
Introduction to electrolysis - electrolytes,
non-electrolytes, electrode equations
You
should be able to:-
(a) describe the electrode products in the electrolysis of:
(i) molten lead (II)
bromide, concentrated hydrochloric acid, concentrated aqueous sodium
chloride, dilute sulphuric acid (as essentially the electrolysis of
water) between inert electrodes;
Electrolysis of acidified
water (dilute sulfuric acid) and some sulfate salts and alkalis
Electrolysis of sodium
chloride solution (brine)
Electrolysis of molten lead(II) bromide
(and other molten ionic compounds)
Electrolysis of hydrochloric acid
and ...
(ii) aqueous copper (II) sulphate using carbon electrodes and using
copper electrodes (as used in the refining of copper);
Electrolysis of copper(II)
sulfate solution and electroplating
The purification of
copper by electrolysis
(b) describe electrolysis in terms of the ions present and reactions at the
electrodes in the examples given;
(c) state the general principles that metals or hydrogen are formed at the
negative electrode (cathode) an that non-metals (other than hydrogen) are formed
at the positive electrode (anode);
(d) predict the likely products of the electrolysis of a specified binary
compound in the molten state or in concentrated aqueous solution;
(e) describe, in outline,
the manufacture of: -
(i) aluminium from pure
aluminium oxide in molten cryolite
The electrolysis of molten aluminium oxide
- extraction of
aluminium from bauxite ore
(ii) chlorine and sodium hydroxide from concentrated aqueous
sodium chloride;
...
Salt -
sodium chloride - extraction - uses of halogens (including industrial
electrolysis of brine)
(f) describe the
electroplating of metals exemplified by copper plating;
Electroplating
coating
conducting surfaces with a metal layer
(g) state two uses of electroplating;
(h) describe the reasons for the use of copper and (steel-cored) aluminium in
cables and why plastics and ceramics are used as insulators
6 ENERGY CHANGES
(Zimbabwe O Level Chemistry 5071)
 You
should be able to:
(a) describe the meaning of enthalpy change in terms of exothermic
(ΔH negative) and endothermic (ΔH positive) reactions;
(b) use the kilojoules, KJ, as a unit of energy;
(c) describe bond breaking as endothermic and bond forming as
exothermic;
(d) state that the burning of fuels, e.g. wood, coal, oil, is
exothermic;
(e) describe hydrogen as a fuel, e.g. in rockets;
(f) describe radioactive isotopes, such as 235U, as a source of
nuclear energy;
(g)
describe the production of electrical energy from simple cess, i.e.
two electrodes in an electrolyte. This should be linked with the
reactivity series;
(h) describe the use of batteries as a convenient, portable energy
source;
(i) describe the use of solver salts in photography as an
endothermic process involving reduction of silver ions to silver;
(j) describe photosynthesis as the reaction between carbon dioxide
and water in the presence of chlorophyll and using sunlight (energy)
to produce glucose
Heat changes in chemical/physical
changes - exothermic and endothermic
Simple cells (batteries)
Fuel Cells e.g. the hydrogen - oxygen fuel cell
7 CHEMICAL REACTIONS
(Zimbabwe O Level Chemistry 5071)
7.1. Speed of Reaction
(how fast? how slow? why? Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the effect of concentration, pressure, particle size
and temperature on the speeds of reactions and explain these effects
in terms of collision between reacting particles.;
(b) describe the effect of catalysts (including enzymes) on the
speeds of reactions;
(c) describe how the above factors are used to explain the danger of
explosive combustion with fine powders (e.g. in flour mills) and
combustible gases (e.g. in mines);
(d) devise a suitable method for investigating the effect of a given
variable on the speed of a reaction;
(e) interpret data obtained from experiments concerned with speed of
reaction.
What do we mean by
the rate/speed of reaction? how can we measure it?
Particle model of the collision theory of
chemical reaction rate factors
Effect of
changing reactant concentration in solution
Effect of
changing pressure in reacting gases
Effect of
changing particle size/surface area & stirring of a solid reactant
Effect of
changing the temperature of reactants
Effect of
using a catalyst in a chemical reaction
Examples of graphs
of rate data, interpretation
Multiple
choice Quiz on the Rates of Chemical Reactions
Crossword on Rates of Reactions *
Answers
Wordfill worksheet on Rates of Chemical Reactions
(1)
matching pair quizzes on Rates of Chemical Reactions and
(2)
7.2. Reversible reactions
(what is a reversible reaction?
Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the idea that some chemical reactions can be reversed
by changing the reaction conditions;
(b) state the idea that some reversible chemical reactions reach a
state of dynamic equilibrium
(c)
predict the effect of changing the conditions of a reversible
reaction at equilibrium.
Reversible Reactions
Reversible reactions and equilibrium
7.3. Redox
(oxidation and reductions definitions,
examples, Zimbabwe O Level Chemistry 5071)
Candidates should be able
to:-
(a) define oxidation and reduction in terms of oxygen/hydrogen
gain/loss;
(b) define redox in terms of electron transfer and changes in
oxidation state;
(c) identify redox reactions in terms of hydrogen/oxygen, and/or
electron, gain/loss;
(d) describe the use of aqueous potassium iodine, acidified
potassium dichromate(VI) and acidified potassium manganate(VII) in
testing for oxidising and reducing agents from the colour changes
produced
Introduction to
oxidation and
reduction and their application to REDOX reactions
8 ACIDS, BASES AND SALTS
(Zimbabwe O Level Chemistry 5071)
8.1. The characteristic
properties of acids and bases
(acids, alkalis, salts, Zimbabwe O Level Chemistry 5071)
You
should be able to:-
(a) describe the meaning of the terms acid and alkali in terms of the ions they
contain or produce in aqueous solution and their effects on indicator paper;
(b) describe neutrality and relative acidity and alkalinity in terms of pH
(whole numbers only) measured using Universal Indicator paper;

Everyday examples of acid-alkali chemistry
pH scale, indicator
colours, ionic theory of acids, alkalis
(bases) & neutralisation
Examples of
acid, neutral or alkaline
solutions
(c) describe the characteristics properties of acids as in reactions with
metals, bases, alkalis, carbonates
Reactions of acids with
metals/oxides/hydroxides/carbonates and neutralisation reactions
The Reactivity
Series of Metals
(d) describe the
characteristic properties of bases as in reactions with acids and
with ammonium salts;
Reactions of bases-alkalis
like sodium hydroxide
(e) describe and explain the importance of controlling the pH of soil;
Multiple choice quiz on pH, Indicators, Acids,
Bases, Neutralisation and Salts
Structured question worksheet on Acid
Reaction word equations and
symbol
equation question
Word
equation answers and
symbol
equation answers
Word-fill worksheet on Acids,
Bases, Neutralisation and Salts
Matching pair quiz on Acids, Bases, Salts and pH
8.2. Types of oxides
(link to metals and non-metals,
Zimbabwe O Level Chemistry 5071)
Candidates should be able
to:
Classify oxides as either acidic, basic or atmospheric relate to
metallic/non-metallic character.
Periodic Table Notes -
an overview, section on metals & non-metals
8.3. Preparation of salts
(methods of making salts, Zimbabwe O
Level Chemistry 5071)
You
should be able to:-
(a) describe the preparation, separation and purification of salts
as examples of some of the techniques in Section 2.2.(b)
(Methods of preparing
salts to illustrate the practical techniques should include the
action of acids with metals, insoluble base and insoluble
carbonates).
(b)
describe the preparation of salts by titration method;
(c) suggest a method of preparing a given salt from suitable
starting materials, given appropriate information.
Making a soluble salt by neutralising a soluble acid with a soluble base (alkali)
Making a soluble salt by from an acid with a metal or
insoluble base – oxide, hydroxide or carbonate
Preparing an
insoluble salt by mixing solutions of two soluble compounds
8.4. Identification of ions and
gases (tests for gases
and ions, Zimbabwe O Level Chemistry 5071)
Candidates
should be able to:
describe and explain the use of the following tests to identify:
(i) aqueous cations; aluminium, ammonium, calcium, copper (ii), iron
(ii), iron (iii) and zinc using aqueous sodium hydroxide and aqueous
ammonia, as appropriate (formulae of complex ions are not required);
(ii) anions; carbonate (by reaction with dilute acid and then
limewater); chloride (by reaction, under acidic conditions, with
aqueous silver nitrate); iodide (by reaction, under acidic
conditions, with aqueous lead (ii) nitrate); nitrate (by reduction
with aluminium to ammonia) and sulphate (by reaction, under acidic
conditions, with aqueous barium ions);
(iii) gases; ammonia (using damp red litmus paper); carbon dioxide
(using limewater); chloride (using damp litmus paper); hydrogen
(using lighted splint); oxygen (using glowing splint) and sulphur
dioxide (using acidified potassium dichromate (IV)).
Quick summary of tests for gases and
ions including equations
chemical
tests for cations and
chemical
tests for anions (more detailed notes, use alphabetical index)
and
TESTS for gases,
water and non–metallic elements (more
detailed notes, use alphabetical index)
9 THE PERIODIC TABLE
(survey of elements of the periodic
table, Zimbabwe O Level Chemistry 5071)
You
should be able to describe the Periodic Table as a method of
classifying elements and its use to predict properties of elements.

Periodic Table Notes -
an overview, groups, periods, metals & non-metals
Multiple choice
quiz on the basics of the Periodic Table
Task sheet worksheet on Periodic Table
history * (answers)
Basic Periodic Table Task
sheet worksheet * (answers)
Gap-fill worksheet on the Periodic Table
Element Symbol-name QUIZ
easier-pictorial
or harder-no
pictures!
Giant Periodic Table crossword puzzle
9.1. Periodic Trends
(trends in the periodic table,
periods, groups, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the changes from metallic to non-metallic character
across a period;
(b) describe the relationship between Group number, number of
valency electrons and metallic/non-metallic character;

Periodic Table Notes -
an overview, groups, periods, metals & non-metals
Matching pair quiz on Atomic and electronic structure and the
Periodic Table
9.2. Group properties
(physical and chemical properties of
alkali metals, halogens, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe lithium, sodium and potassium in Group 1 (the alkali
metals) as a collection of relative soft, low density metals showing
a trend in melting points and in reaction with water
(b)
predict the properties of elements in Group 1, given data, where
appropriate;
Group 1
Alkali Metals
- physical and chemical properties
Multiple choice quiz on the Group 1 Alkali
Metals
Word-fill worksheet on the
Group 1 Alkali Metals
(c) describe chlorine,
bromine and iodine in Group VII (the halogens) as a collection of
diatomic non-metals showing a trend in colour, state and their
displacement reactions with other halide ions;

(d)
predict the properties of elements in Group VII, given data, where
appropriate;
(e) identify trends in other Groups given information about the
elements concerned;
Group 7
Halogens - physical and chemical properties
Multiple choice
quiz on the Group 7 Halogens
A Group 7 "Halogens" task sheet worksheet * (answers)
Word-fill work sheet on the Halogens
The
Halogens (matching pair quiz on their appearance)
9.3. Noble gases
(properties of noble gases, Zimbabwe
O Level Chemistry 5071)
You
should be able to:
(a) describe the noble gases as being uncreative;
(b) describe the uses of the noble gases in providing an inert
atmosphere, e.g. argon in lamps; helium for filling balloons
Group 0
Noble Gases
Multiple choice quiz on Group 0 The Noble Gases
Wordfill worksheet on the
Noble Gases (answers)
10 METALS
(Zimbabwe O Level Chemistry 5071)
10.1.
Properties of metals
(characteristic metallic properties, Zimbabwe O Level Chemistry 5071)
Periodic Table Notes -
section on typical properties of metals & non-metals
Metallic
bonding, properties and uses of metals
10.2. Reactivity series
(reactivity of metals with water, acids, salt solutions, Zimbabwe O
Level Chemistry 5071)
You should be able to:-
(a) place calcium, copper, (hydrogen), iron, magnesium, potassium,
silver, sodium and zinc in order to reactivity by reference to:
(i) the reactions, if any, of the metals with water or steam, dilute
hydrochloric acid;
(ii) the reduction, if any, of their oxides with carbon and with
oxygen;
(b) describe the reactivity series as related to the tendency of a
metal to form its positive ion, illustrated by its reaction with:
(i) the aqueous ions of the other listed metals;
(ii) the oxides of the other listed metals;
(c) describe the action of heat on the carbonates of the listed
metals
(d) account of the apparent unreactivity of aluminium in terms of
the presence of an oxide layer which adheres to the metal;
(e) deduce an order or reactivity from a given
set of experimental results.
The Reactivity
Series of Metals
Metal Reactivity Series
Experiments-Observations
The corrosion of metals and the prevention of iron rusting
Limestone: Section on the
thermal decompositions of carbonates
10.3. Extraction and uses of
metals (how do we
extract metals from their ores?, Zimbabwe O Level Chemistry 5071)
You should be able to:
 (a)
describe the ease of obtaining metals from their ores by relating
the elements the reactivity series;
Introduction to Metal Extraction
(b) describe the essential reactions in the extraction of iron from
haematite in the blast furnace;
(c) describe the ideas of changing the properties of iron by the
controlled use of additives to form alloys called steels;
Extraction of Iron and Steel Making
(d) state the use of mild steel (car bodies and machinery) and
stainless steel (chemical plant and cutlery)
(e)
describe, in outline, the extraction of aluminium from pure
aluminium oxide;
Extraction of Aluminium
(f) state the uses of
aluminium: in the manufacture of aircraft because of it strength and
low density;
How can
metals be made more useful? (alloys of Al, Fe, steel etc.)
(g)
state the uses of zinc for galvanising and for making brass (with
copper);
(h) state the uses of copper related to its properties, e.g.
electrical wiring.
Transition
Metals eg uses of iron and copper plus mention of aluminium
11
NON-METALS (Zimbabwe O
Level Chemistry 5071)
11.1. Hydrogen
(chemistry and uses of hydrogen, Zimbabwe O Level Chemistry 5071)
You should be able to:
(a) describe the formation of hydrogen as a product of the reaction
between:-
(i)
reactive metals and water
(ii) metals and acids
The Reactivity
Series of Metals
Reactions of acids with
metals
Metal Reactivity Series
Experiments-Observations
(b) describe the formation
of hydrogen as a product of electrolysis of certain aqueous
solutions related to the ions present and their position in the
reactivity series;
Electrolysis of acidified
water (dilute sulfuric acid) and some sulfate salts and alkalis
(c) describe, in outline, the manufacture of hydrogen from the reaction between
methane and steam;
The
Haber Synthesis of ammonia - including manufacture and
use of hydrogen
(d) state
the uses of hydrogen in the manufacture of ammonia, and of margarine
from unsaturated vegetable oils, and as a fuel in rockets;
(e) describe, in outline, he purification of the water supply in
terms of filtration and chlorination;
Water
cycle, potable water, water treatment, pollution, tests for ions in water
(f) state some of the uses of water in industry and in the home;
(g) describe a chemical test for water - turns white anhydrous copper
sulfate blue
11.2. Oxygen
(air pollution, preventing rusting,
Zimbabwe O Level Chemistry 5071)
You should be able to:
(a) describe, in simple terms, the ideas of respiration, combustion
and rusting;
Types of chemical reactions
and
QUIZ on types of chemical
reaction
(b) describe the volume composition of clean air in terms of 79%
nitrogen, 20% oxygen, with the remainder being noble gases (with
argon as the main constituent), carbon dioxide and variable amounts
of water vapour;
(c) name common pollutants of air (carbon monoxide, sulphur dioxide,
oxides of nitrogen, e.g. NO2, and led compounds);
Our atmosphere - composition, determining % oxygen, uses of gases in air
(d)
state the source of each of these pollutants:
(i) carbon monoxide from
the incomplete combustion of carbon – containing substances;
(ii) sulphur dioxide from the combustion of fossil fuels which
contain sulphur compounds (leading to ‘acid rain’);
(iii) oxides of nitrogen and lead compounds from car exhausts
(e) state the adverse effect
of acidic pollutants on buildings and plants, and of carbon
monoxide;
Air pollution - sulfur oxides, nitrogen
oxides, acid rain
Air pollution -
incomplete combustion, carbon monoxide & soot
(f) describe the separation of oxygen and nitrogen from liquid air by fractional
distillation;
(g) name the uses of oxygen in making steel, oxygen tents in hospitals, and with
acetylene ( hydrocarbon) in welding;
(h) describe paint and other coatings, including galvanising, as methods of rust
prevention;
(i) describe sacrificial protection in terms of the reactivity series of metals.
The corrosion of metals and the prevention of iron rusting
11.3. Nitrogen
(Zimbabwe O Level Chemistry 5071)
You should be able to:
(a) state the use of nitrogen in the manufacture of ammonia;
(b) describe the essential conditions for the manufacture of ammonia
by the Haber process;
(c)
describe the displacement of ammonia from its salts;
(d) state the need for nitrogen, phosphorus and potassium compounds
in plant life;
(e) name the uses of ammonia
in the manufacture of fertilisers such as ammonium sulphate and
nitrate;
The
Haber Synthesis of ammonia - nitrogen fixation
Manufacture and uses of fertilisers,
preparation of ammonium salts, NPK fertilisers-environmental problems
11.4. Sulphur
(reactions, uses and manufacture of
sulfuric acid, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) state the uses of sulphur dioxide as a bleach in the manufacture
of wood pulp for papers; as a food preservative (by killing
bacteria);
(b) describe the manufacture of sulphuric acid as a typical acid
from sulphur by the Contact process;
(c) describe the properties of dilute sulphuric acid;
(d) state the uses of sulphuric acid as in the manufacture of
detergents and fertilisers.
Reactions of acids with
metals/oxides/hydroxides/carbonates and neutralisation reactions
Contact Process
for manufacturing sulfuric acid, the importance of sulphuric acid
11.5. Chlorine
(uses of salt - sodium chloride,
Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) name some sources of sodium chloride;
(b) describe the importance of sodium chloride as a source for
chlorine and sodium hydroxide;
(c) state the main uses of chlorine in sterilising water;
manufacturing plastics, e.g. pvc; making domestic bleaches
Salt -
sodium chloride - extraction - uses of halogens (including industrial
electrolysis of brine)
11.6. Silicon
(silica, Zimbabwe O Level Chemistry
5071)
You
should be able to:
(a) describe silicon as a common element in most rocks (being
combined with oxygen);
(i) as silicon (IV)
oxide (silicon dioxide), e.g. quartz
(ii) as complex silicates, e.g. mica
(b) describe sand as impure
form of silicon (IV) oxide;
(c) state the use of sand in making glass (a mixture of silicates)
and as a source of silicon (by reduction);
(d) state the uses of silicon in semiconductors (for electronics)
and for making silicones
(e) state that different silicones are able to exist as oils, waxes
or plastics
(f) explain the fire resistance o a silicone plastic to the nature
of the combustion product and compare this to carbon-based polymers;
Covalent
bonding and giant structures
- silica
11.7. Carbon and carbonates
(structure and uses of diamond,
graphite, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) name the allotropes of carbon as graphite and diamond
(b) state use of relate their structures to the uses of graphite
e.g. as a lubricant and diamond in cutting
(c) describe the manufacture of lime (calcium oxide) from calcium
carbonate (limestone) in terms of the chemical reaction involved
(d) state some uses of lime and slaked lime as in treating acidic
soil and neutralizing acidic industrial waste products
(e) state the uses of calcium carbonate in the manufacture of iron,
glass and of cement
Covalent
bonding and giant structures and
their properties and uses - diamond and graphite
Notes on limestone, lime and uses,
glass etc.
12 ORGANIC CHEMISTRY
(organic chemistry for Zimbabwe O
Level Chemistry 5071)

12.1. Name of compounds
(naming and structure of organic compounds, Zimbabwe O Level Chemistry
5071)
You
should be able to:
(a) name, and draw the structure of, the unbranched alkanes, alkenes
(not cis-trans), alcohols and acids containing up to four carbon
atoms per molecule and the products of the reactions stated in
Sections 12.4 to 12.6
(b) state the type of compound present, given a chemical name ending
in –ane, -ene, -ol, -oic acid, or given a molecular structure
Introduction to Organic Chemistry - homologous series - functional groups
Alkanes
- saturated hydrocarbons, structure and names
Alkenes - unsaturated hydrocarbons
- structure and names
Alcohols -
structures and names
Carboxylic acids - structure and names
12.2. Fuels
(fossil fuels from crude oil and natural
gas, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) name natural gas and petroleum as sources of fuels;
(b) name methane as the main constituent of natural gas;
(c) describe petroleum as a mixture of hydrocarbons and its
separation into useful fraction b fractional distillation;
(d) name the uses of the fractions: petrol (gasoline) fraction for
fuel in cars; paraffin (kerosene) fraction for oil stoves and
aircraft fuel for fuel in diesel engines: lubricating fraction for
lubricants and making waxes and polishes: bitumen for making roads.
Fossil Fuels
Fractional distillation of crude oil &
molecular properties and uses of fractions
12.3. Homologous series
(organic chemistry - homologous
series, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the general characteristics of a homologous series
(b) describe and identify (given molecular structures) isomerism
Introduction to Organic Chemistry - homologous series - functional groups
Isomerism in organic
chemistry
(advanced page, but see O level pages for alkanes, alkenes, alcohols
and carboxylic acids)
12.4. Alkanes
(chemistry of alkanes, Zimbabwe O
Level Chemistry 5071)
You
should be able to:
(a) describe the properties of alkanes (exemplified by methane) as
being generally unreactive expect in terms of burning and
substitution by chlorine;
(b) draw the structures of branched and unbranched alkanes
containing four or five carbon atoms per molecule.
Alkanes
- saturated hydrocarbons, structure and reactions including combustion
12.5. Alkenes
(chemistry of alkenes, Zimbabwe O
Level Chemistry 5071)
You
should be able to:
(a) describe the manufacture of alkenes and of hydrogen by cracking;
(b) describe the properties of alkenes in terms of burning;
polymerisation; addition reactions with bromine, steam and hydrogen
(margarine manufacture, considered as the addition of hydrogen to
unsaturated vegetable oils in order to give a solid product);
(c) distinguish between saturated and unsaturated hydrocarbons from
molecular structures; by using aqueous bromine;
(d) describe the formation of poly(ethene) as an example of addition
polymerisation of monomer units;
(e) name some uses of poly(ethene) as a typical plastic, e.g.
plastic bags.
Alkenes - unsaturated hydrocarbons
- structure and reactions
Addition polymers, plastics, uses and problems
including poly(ethene)
12.6. Alcohol
(properties and chemistry of
alcohols, Zimbabwe O Level Chemistry 5071)
You
should be able to:
(a) describe the formation of ethanol by fermentation and by the catalytic
addition of steam to ethane;
(b) describe the properties of ethanol in terms of burning and of oxidation;
(c) name the uses of ethanol as a solvent; as a fuel.
Alcohols -
structures including ethanol
- manufacture, properties and reactions
BIOFUELS
12.7. Acids
(chemistry of carboxylic acids, Zimbabwe O
Level Chemistry 5071)
You
should be able to:
(a) describe the formation of ethanoic acid by the oxidation of
ethanol by
(i) the action of
atmospheric oxygen
(ii) acidified potassium dichromate (VI)
(b) describe ethanoic acid
as an acid
(c) describe the reaction of ethanoic acid ethanol to give an ester
(ethyl ethanoate)
Carboxylic acids and esters,
structure and reactions
12.8. Macromolecules
(Zimbabwe O Level Chemistry 5071)
You should be able to
describe macromolecules in terms of large molecules built up form
small units, different macromolecules having different units and/or
different linkages.
12.8.
(a) Synthetic Polymers (Zimbabwe
O Level Chemistry 5071)
You
should be able to:

(i) deduce the structure of the polymer product from a given alkene
and vice versa
(ii) describe the formation of nylon (a polyamide) and Terylene (a
polyester) by condensation polymerization, know the simplified
representations of the structure of nylon and Terylene
(details
of manufacture and mechanism of these polymerization are not
required)
(iii) name some typical uses of man-made fibres such as nylon and
Terylene, e.g. clothing

(iv) describe the pollution problems caused by non-biodegradable
plastics
Addition polymers, plastics, uses and problems,
environmental problems, including poly(ethene)
Comparing addition
polymers and condensation polymers, thermosets, fibres, thermosoftening etc.
12.8. (b) Natural macromolecules
(carbohydrates, proteins, fats,
Zimbabwe O Level Chemistry 5071)
You should be able to:
(i) name proteins, fats and carbohydrates as the main constituents
of food
(ii) describe proteins as possessing the same (amide) linkages as
nylon but with different units
(iii) describe the hydrolysis of protein to amino acids (structures
and names not required)
(iv) describe fats (and vegetable oils) as esters possessing the
same linkages as Terylene but with different structures
(v) describe soap as a product of hydrolysis of fat
(vi) describe the carbohydrate starch as a macromolecule represented
as being formed by the condensation polymerization of smaller
carbohydrate units called sugars - know the simplified
representation of starch molecules
(vii) describe the acid hydrolysis of carbohydrates such as starch
to given simple sugars
(viii) describe the fermentation of simple sugars to produce ethanol
(and carbon dioxide) (Candidates will not be expected to give the
molecular formulae of sugars)
(ix)
describe, in outline, the uses of chromatography in separating and
identifying the products of hydrolysis of carbohydrates and proteins
Natural Molecules - carbohydrates - sugars
- starch
Amino acids, proteins,
enzymes & chromatography
Oils, fats,
margarine and soaps
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