Chemical reactions of the alkenes

2 marks · Easy

An alkene has 15 carbon atoms in its molecule. Calculate the number of hydrogen atoms in one molecule of this alkene. Show your working.

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30 (±0)

Common mistakes: 32; 28

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Marking points

M1 · 1 mark · Uses general formula CnH2n to set up calculation (number of hydrogens = 2 × number of carbons).

A1 · 1 mark · Correctly calculates 2 × 15 = 30 hydrogen atoms.

Worked solution

General formula for alkenes is CnH2n.

There are 30 hydrogen atoms.