Question

Calculate the free energy change for the following reaction at $300\, K$.
$ 2CuO(s) \to Cu_2O(s) + \frac{1}{2}O_2(g)$
Given, $ \Delta H=145.6\,kJ\,mol^{-1} $ and $ \Delta S=116\,Jk^{-1}mol^{-1} $

• A. $ 110.8\,kJ\,mol^{-1} $
• B. $ 221.5\,kJ\,mol^{-1} $
• C. $ 55.4\,kJ\,mol^{-1} $
• D. $ 145.6\,kJ\,mol^{-1} $

Answer 1

Answer: (A)

$ \Delta G=\Delta H-T\Delta S $
$ =145.6\times 10^{3}-300\times 116 $
$ =145.6\times 10^{3}-34.8\times 10^{3} $
$ =110.8\times 10^{3}J\,mol^{-1} $
$ =110.8\,kJ\,mol^{-1} $