Formulae & Functional Groups

  • M/J 2017/P12/Q38

Molecules 1–4 are unbranched hydrocarbons

1 C10H22

2 C10H20

3 C9H20

4 C8H16

Which row correctly identifies these hydrocarbons as alkanes or alkenes?

Answer: ​​ B

Explaination:

Alkane is a saturated hydrocarbon and its general formula is CnH2n+2​​ whereas, Alkene is an unsaturated hydrocarbon and its general formula is CnH2n. So, by using general formula, putting the value of “n” i.e. number of carbon atoms present in the molecular structure we can identify whether its alkane or alkene.