The hydrocarbon formed when sodium propanoate and soda lime are heated together:

Ethane

Reason —

$\underset{\text{sodium propionate}}{\text{C}\text{H}_3\text{-C}\text{H}_2\text{.COONa}} + \underset{\text{sodalime}}{\text{NaOH}} \xrightarrow[\Delta]{\text{CaO}} \underset{\text{ethane}}{\text{C}_2\text{H}_6} + \text{Na}_2\text{CO}_3$