14.8 (b) Natural macromolecules Food’s main constituents are proteins, fats and carbohydrates. Proteins contain the same linkages (amide links) as nylon, but with different units. Similarly, lipids and terylene both have ester links but different units. The structure...
14.8 (a) Synthetic polymers Uses of plastics: Polymer Example of uses polythene plastic bags and gloves, clingfilm (low density), mugs, bowls, chairs, dustbins (high density) polychloroethane (PVC) water pipes, wellingtons, hoses, covering for electricity cables...
Acids Formation of ethanoic acid: -oxidation of ethanol -with acidified potassium mangenate (VII) Ethanoic acid is a typical weak acid: it has a high (as in closer to 7 than 1) pH for an acid, and only dissociates a little bit. Carboxylic acids react with alcohols to...
Macromolecules Macromolecules are large molecules built up from small units (monomers). Different macromolecules have different units and/or different linkages (that’s all you have to know!) For example glucose (the small unit) can join together to make starch or...
14.5 Alkenes Cracking: is a thermal decomposition reaction, in which an alkene (and sometimes hydrogen) are produced from an alkane. Cracking always produces a short chain compound with a C=C bond. Cracking of ethane will give ethene and hydrogen. In the lab it looks...
14.5 Alcohols Ethanol can be formed in to ways: By fermentation: enzymes in yeast break down glucose (a simple sugar) to ethanol and carbon dioxide, giving out heat (exothermic). This can be done with any substance that contains cellulose, starch or It is done...
Names of compounds Name and draw the structure of the following compounds: Name and draw the structure of the following compounds: Name Chemical formula Structure methane CH4 ethane C2H6 ethene C2H4 ethanol C2H5OH ethanoic acid CH3COOH Name ending →...
Fuels Fuels to know: -coal -natural gas (main constituent is methane) -petroleum (a mixture of hydrocarbons which can be separated into fractions): refinery gas – bottled gas for heating and cooking gasoline fraction – fuel (petrol) in cars naphtha fraction – making...
Homologous series Homologous series: ‘family’ of similar compounds with similar properties due to the presence of the same functional group. Characteristics of a homologous series: -all the compounds fit the same general formula -the chain length increases by 1 each...
14.4 Alkanes Each carbon atoms in an alkene has four covalent single bonds – this makes them quite unreactive. They only have two reactions: -combustion this can either be: -complete: meaning there is enough oxygen supply so water and carbon dioxide form. e.g. CH4 +...
Organic chemistry This is what is on the syllabus only, but I have made more concise notes which cover all of organic chemistry in the book chapters 17 and 18 BASICS (stuff that isn’t in the syllabus but is important): Alkane – general formula CnH2n+2 Alkene -...