51.8k views
3 votes
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

User Kuba Orlik
by
6.0k points

2 Answers

2 votes

Answer:

See the explanation for the answer.

Step-by-step 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.

User Ininiv
by
5.9k points
5 votes

Answer:

Step-by-step explanation:

find the solution below

6. At high temperatures, alkanes can undergo dehydrogentation to produce alkenes. This-example-1
User Karel Kubat
by
5.8k points