Question

For the reaction at $298 \, \text{K}$, $2\text{A} + \text{B} \rightarrow \text{C}$. $\Delta H = 400 \, \text{kJ mol}^{-1}$ and $\Delta S = 0.2 \, \text{kJ mol}^{-1} \, \text{K}^{-1}$. The reaction will become spontaneous above ____ $\text{K}$.

Answer 1

Correct Answer: 2000

For spontaneity, we use the Gibbs free energy equation where \( \Delta G = 0 \) at the threshold temperature for spontaneity:

\[ T = \frac{\Delta H}{\Delta S} = \frac{400}{0.2} = 2000 \, \text{K} \]