very-high Formula questions (1-2 marks): Use CₙH₂ₙ₊₂ to determine molecular formula. Must show working.
high Saturated/unsaturated distinction (2 marks): Define saturated as "only single C-C bonds" and contrast with alkenes.
high Drawing structures (2-3 marks): Draw displayed formula with each carbon making exactly 4 bonds.
Common exam question: "Explain what is meant by 'saturated'" — Answer must include "only single C-C bonds" (not just "full of hydrogen").
Edexcel 1CH0: Examined in Paper 2 (1CH0/2). Properties of alkanes and their combustion (complete and incomplete) are tested; Edexcel also covers the environmental impact of burning fossil fuels. In Edexcel-style questions, the command word "Suggest" appears frequently — use your chemistry knowledge to apply to an unfamiliar context.
This exam focus covers Exam Focus: Alkanes within Alkanes for GCSE Chemistry. Topic 38: Alkanes It is section 10 of 12 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Practice questions for Alkanes
What is the general formula for the alkane homologous series?
Explain why the boiling point of alkanes increases as the chain length increases.