Question

The value of ΔG° at 181.0 °C for the formation of calcium chloride from calcium metal and chlorine gas is ________ kJ/mol. At 25.0 °C for this reaction, ΔH° is -795.8 kJ/mol, ΔG° is -748.1 kJ/mol, and ΔS° is -159.8 J/K.

Answer 1

Answer:

$\Delta G^{0}$ at 181.0 $^{0}\textrm{C}$ is -723.3 kJ/mol.

Explanation:

We know, $\Delta G^{0}=\Delta H^{0}-T\Delta S^{0}$

where, T is temperature in kelvin.

Let's assume $\Delta H^{0}$ and $\Delta S^{0}$ does not change in the temperature range 25.0 $^{0}\textrm{C}$  - 181.0 $^{0}\textrm{C}$.

$181.0^{0}\textrm{C}$ = (273+181.0) K = 454.0 K

Hence, at 181.0 $^{0}\textrm{C}$, $\Delta G^{0}=(-795.8kJ/mol)-[(454.0 K)\times (-159.8\times 10^{-3}kJ/K.mol)]$

        = -723.3 kJ/mol