Question detail

Which statement best describes crude oil according to the AQA GCSE Chemistry specification?

Try the question, check the answer, then read the explanation to understand the curriculum point.

Show answer Topic hub Objective page

At a glance

MCQ

Type

practice

Style

Topic

Carbon compounds as fuels and feedstock

Question

A. It is a single pure compound.
B. It is a finite resource found in rocks.
C. It is a mixture of a very large number of compounds.
D. It is mainly composed of water and salts.

Answer

The correct option is It is a mixture of a very large number of compounds..

Explanation

The correct option is It is a mixture of a very large number of compounds.. It is a mixture of a very large number of compounds. is correct because it directly supports the approved learning objective to describe crude oil as a mixture of a very large number of compounds. This belongs to Crude oil, hydrocarbons and alkanes within Carbon compounds as fuels and feedstock, so the answer must use the correct organic chemistry context. The other options are incorrect when they confuse the organic family, formula type, reaction condition, product, or property being tested. Keep molecular formula, structural formula, displayed formula, and general formula distinct. Do not confuse alkanes with alkenes, saturated with unsaturated, cracking with combustion, polymers with monomers, or hydrocarbons with oxygen-containing alcohols and carboxylic acids. When formulae are used, preserve the stored notation exactly and explain the GCSE chemistry idea in words rather than using unsupported displayed-formula diagrams.

Common mistake

Misidentifying crude oil as a single compound

Students often think crude oil is a single, pure substance rather than a complex mixture of many hydrocarbons and other compounds.

Explain that crude oil is a heterogeneous mixture containing thousands of different molecules, mainly hydrocarbons, and that this diversity is why fractional distillation is needed to separate useful fractions.

Related flashcards

Flashcard 1 of 5

Press Space to flip, arrows to move