Conventional liquid fuels derived from crude oil consist of a mixture of hydrocarbons. Modern alternative fuels and additives often contain other elements, and crude oil fractions must be desulfurised to remove harmful sulfur-containing impurities.
Which of the following chemical formulae represents a hydrocarbon?
CH3(CH2)4COOCH3\text{CH}_3(\text{CH}_2)_4\text{COOCH}_3CH3(CH2)4COOCH3
CH3CH2CH(CH3)CH2CH3\text{CH}_3\text{CH}_2\text{CH}(\text{CH}_3)\text{CH}_2\text{CH}_3CH3CH2CH(CH3)CH2CH3
CH3CH2CH2SH\text{CH}_3\text{CH}_2\text{CH}_2\text{SH}CH3CH2CH2SH
CH3CH2CH2OH\text{CH}_3\text{CH}_2\text{CH}_2\text{OH}CH3CH2CH2OH
130 exam-style questions on Edexcel GCSE Chemistry 9.1 Fuels, covering 9.1.1 Hydrocarbons and crude oil, 9.1.2 Fractional distillation of crude oil and its fractions, 9.1.3 The alkanes as a homologous series, 9.1.4 Complete and incomplete combustion, 9.1.5 Pollutants from burning fuels, 9.1.6 Hydrogen as a fuel and non-renewable fossil fuels, and 9.1.7 Cracking of larger alkanes. Each one has a worked solution and a mark scheme showing where the marks go.