Question

Classify the following compounds as alkanes, alkenes and alkynes. [3 MARKS]

${\text{C}}_5{\text{H}}_{1}2$ , ${\text{C}}_2{\text{H}}_4$, ${\text{C}}_3{\text{H}}_4$, ${\text{C}}_3{\text{H}}_8$, ${\text{C}}_4{\text{H}}_8$, ${\text{C}}_5{\text{H}}_8$

Answer 1

Each point: 1 Mark

General formula for alkanes, alkenes and alkynes respectively are ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n+2}}$, ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n}}$ and ${\text{C}}_{\text{n}}{\text{H}}_{2n-2}$.

Therefore, in the given compounds:

1. Alkanes : ${\text{C}}_5{\text{H}}_{12}$, ${\text{C}}_3{\text{H}}_8$

2. Alkenes : ${\text{C}}_2{\text{H}}_4$, ${\text{C}}_4{\text{H}}_8$

3. Alkynes : ${\text{C}}_3{\text{H}}_4$, ${\text{C}}_5{\text{H}}_8$