Question

At high temperatures, alkanes can undergo dehydrogenation to produce alkenes. For example: This reaction is used industrially to prepare ethylene while simultaneously serving as a source of hydrogen gas. Explain why dehydrogenation only works at high temperatures.

Answer 1

Answer:

Dehydrogenation of alkanes is endothermic

Explanation:

The dehydrogenation of alkanes is an endothermic reaction. The enthalpy change for the reaction is highly positive.

Recall that for an endothermic reaction, increase in temperature increases the rate of forward reaction.

As a result of that, the dehydrogenation of alkanes proceeds in the foward direction at elevated temperatures.