The origin of crude oil
3 marks · EasyCrude oil is an important natural resource. Answer all parts.
State what crude oil is a mixture of.
Give the names of the two elements found in all hydrocarbons in crude oil.
Hydrocarbon molecules in crude oil have different sizes. Name one way in which large hydrocarbon molecules differ from small ones.
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(a) Hydrocarbons
(b) Carbon and hydrogen
(c) Larger molecules have higher boiling points
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Marking points
B1 (a) · 1 mark · States that crude oil is a mixture of hydrocarbons
B1 (b) · 1 mark · Names both elements: carbon and hydrogen
B1 (c) · 1 mark · Names any property that changes with molecule size (e.g., boiling point, viscosity, flammability, volatility, colour)
Worked solution
a) Crude oil is a mixture of hydrocarbons.
b) The elements are carbon and hydrogen.
c) Large hydrocarbon molecules have a higher boiling point than small molecules.