Question

6. At high temperatures, alkanes can undergo dehydrogentation to produce alkenes. 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 using approximately 20 words or less. (5 poin

Answer 1

Answer:

Explanation:

find the solution below

Answer 2

Answer:

See the explanation for the answer.

Explanation:

The given dehydrogenation is an endothermic reaction. That is ΔH is positive.

The number of moles of gaseous products = 2

The number of moles of gaseous reactants = 1

So the change in entropy of dehydrogenation reaction is positive, that is Δs is positive.

For a reaction to be spontaneous, the change in Gibb's free energy should be negative, that is ΔG is negative.

We know that ΔG = ΔH - TΔs

Since ΔH is positive and Δs is positive, for ΔG is negative only if T Δs is greater than  ΔH.

This will happen only if temperature(T) is higher.

Hence dehydrogenation reaction takes place at higher temperature.