HOME PAGE * KS3 SCIENCES * GCSE BIOLOGY CHEMISTRY PHYSICS * ADVANCED LEVEL CHEMISTRY

SPECTROSCOPY INDEXES  *  All Advanced Organic Chemistry Notes  *  [SEARCH BOX]

Advanced Organic Chemistry: Mass spectrum of ethyl ethanoate

Scroll down and take time to study the content and/or follow links or [Use the website search box]

The mass spectrum of ethyl ethanoate (ethyl acetate)

Doc Brown's Chemistry Advanced Level Pre-University Chemistry Revision Study Notes for UK IB KS5 A/AS GCE advanced A level organic chemistry students US K12 grade 11 grade 12 organic chemistry courses involving molecular spectroscopy analysing mass spectra of ethyl ethanoate

email doc brown

Use your mobile phone or ipad etc. in 'landscape' mode

This is a BIG website, you need to take time to explore it

Mass spectroscopy - spectra index

mass spectrum of ethyl ethanoate fragmentation pattern of m/z m/e ions for analysis and identification of ethyl acetate image diagram doc brown's advanced organic chemistry revision notes 

Interpreting the fragmentation pattern of the mass spectrum of ethyl ethanoate

Ethyl ethanoate C4H8O2  (c) doc b , (c) doc b , (c) doc b , (c) doc b 

[M]+ is the molecular ion peak (M) with an m/z of 88 corresponding to [C4H8O2]+, the original ethyl ethanoate molecule minus an electron, [CH3COOCH2CH3]+.

You might see a tiny M+1 peak at m/z 89, corresponding to an ionised ethyl ethanoate molecule with one 13C atom in it i.e. an ionised ethyl ethanoate molecule of formula 13C12C3H8O2

Identifying the species giving the most prominent peaks (apart from M) in the fragmentation pattern of ethyl ethanoate.

m/z value of [fragment]+ 73 70 61 ? 45 43 42 29 27 15
[molecular fragment]+ [C2H5O-C=O]+ [C4H6O]+ [C2H4O2]+ [C2H5O]+ [CH3C=O]+ [CH2CO]+ [CH3CH2]+ [C2H3]+ [CH3]+

Analysing and explaining the principal ions in the fragmentation pattern of the mass spectrum of ethyl ethanoate

Atomic masses: H = 1;  C = 12 (13 for ~1 in 100);  O = 16

Bond enthalpies = kJ/mol: C-C = 348;  C-H = 412;  C-O = 360;  C=O  = 743

Explaining the principal fragments of the mass spectrum of ethyl ethanoate

The most abundant ion peaks

Formation of m/z 73 ion: 

[CH3COOCH2CH3]+  ===>  [C2H5O-C=O]+  +  CH3

C-C bond scission in the parent molecular ion, mass change 88 - 15 = 73.

Formation of m/z 70 ion: 

[CH3COOCH2CH3]+  ===>  [C4H6O]+  +  H2O

Elimination of water from the parent molecular ion?, mass change 88 - 18 = 70

Formation of m/z 45 ion: 

[CH3COOCH2CH3]+  ===>  [C2H5O]+  +  CH3CO

C-C bond scission in the parent molecular ion, mass change 88 - 43 = 45.

Formation of m/z 43 ion: 

[CH3COOCH2CH3]+  ===>  [CH3C=O]+  +  CH3

C-C bond scission in the parent molecular ion, mass change 88 - 45 = 43.

The m/z 43 ion is the base peak ion, the most abundant 'stable' ion fragment.

Formation of m/z 15 ion: 

[CH3COOCH2CH3]+  ===>  [CH3]+  +  C3H5O2

C-C bond scission in the parent molecular ion, mass change 88 - 73 = 15


Key words & phrases: mass spectra of ethyl acetate how to interpret and explain the mass spectrum of ethyl ethanoate m/z m/e base peaks, image and diagram of the mass spectrum of ethyl ethanoate, details of the mass spectroscopy of ethyl ethanoate,  low and high resolution mass spectrum of ethyl ethanoate, prominent m/z peaks in the mass spectrum of ethyl ethanoate, comparative mass spectra of ethyl ethanoate, the molecular ion peak in the mass spectrum of ethyl ethanoate, analysing and understanding the fragmentation pattern of the mass spectrum of ethyl ethanoate, characteristic pattern of peaks in the mass spectrum of ethyl ethanoate, relative abundance of mass ion peaks in the mass spectrum of ethyl ethanoate, revising the mass spectrum of ethyl ethanoate, revision of mass spectroscopy of ethyl ethanoate, most abundant ions in the mass spectrum of ethyl ethanoate, how to construct the mass spectrum diagram for abundance of fragmentation ions in the mass spectrum of ethyl ethanoate, how to analyse the mass spectrum of ethyl ethanoate, how to describe explain the formation of fragmented ions in the mass spectra of ethyl ethanoate equations for explaining the formation of the positive ions in the fragmentation of the ionised molecule of ethyl ethanoate explaining the m/z ion fragmentation pattern in the mass spectrum of ethyl ethanoate


Links associated with ethyl ethanoate

The infrared spectrum of Ethyl ethanoate (ethyl acetate)

The H-1 NMR spectrum of Ethyl ethanoate (ethyl acetate)

The C-13 NMR spectrum of Ethyl ethanoate (ethyl acetate)

The chemistry of CARBOXYLIC ACIDS and DERIVATIVES revision notes INDEX

Mass spectroscopy index

ALL SPECTROSCOPY INDEXES

All Advanced Organic Chemistry Notes

Use My Google search site box

Email doc b: chem55555@hotmail.com

 Doc Brown's Chemistry 

*

TOP OF PAGE