Spontaneous Reaction Video Lessons

Concept

# Problem: For the reactionC2H6 (g) → C2H4 (g) + H2 (g) ΔH° is +137 kJ/mol and ΔS° is +120 J/K • mol. This reaction is ________.A) spontaneous at all temperaturesB) nonspontaneous at all temperaturesC) spontaneous only at high temperatureD) spontaneous only at low temperature

###### FREE Expert Solution

We’re being asked to determine the spontaneity of given reaction given its ΔH and  ΔS.

C2H(g) → C2H4 (g) + H2 (g)

The statements given describe the spontaneity of the reaction at different temperatures

Recall that when ΔH and ΔS are given, we can determine the spontaneity of the reaction based on their signs

We can use the Punnett square shown below:

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###### Problem Details

For the reaction

C2H(g) → C2H4 (g) + H2 (g)

ΔH° is +137 kJ/mol and ΔS° is +120 J/K • mol. This reaction is ________.

A) spontaneous at all temperatures

B) nonspontaneous at all temperatures

C) spontaneous only at high temperature

D) spontaneous only at low temperature