Question

Consider the following reaction: C2H4(g)+H2(g)→C2H6(g) ΔH=−137.5kJ; ΔS=−120.5J/K Calculate ΔG at 25 ∘C and determine whether the reaction is spontaneous. Express the free energy change in joules to four significant figures.

Answer 1

Answer:

* $\Delta G=-101.6kJ$

* Spontaneous reaction.

Explanation:

Hello,

In this case, for the given reaction, we can compute the Gibbs free energy by using the shown below equation:

$\Delta G=\Delta H-T\Delta S$

In such a way, we proceed as follows with the proper units:

$\Delta G=-137.5kJ-(25+273.15)K*(-120.5\frac{J}{K}*\frac{1kJ}{1000J} )\\\\\Delta G=-101.6kJ$

Therefore, since the Gibbs free energy of reaction is less than 0, the reaction is said to be spontaneous.

Best regards.