Question

The standard entropy change for the reaction $4Fe\left(s\right)+3O_2\left(g\right)\to 2F{e}_2{O}_3\left(s\right)$ is $–550J{K}^{–1}$ at $298K$.
[Given: The standard enthalpy change for the reaction is $–165kJmo{l}^{–1}]$. The temperature in $K$ at which the reaction attains equilibrium is . (Nearest Integer)

Answer 1

At equilibrium $\Delta G$ = 0.
So, from Gibbs-Helmholtz equation,
$\Delta G=\Delta H-T\times \Delta S$
$\Delta S=\frac{\Delta H}{T}$
$\therefore T=\frac{\Delta H}{\Delta S}$
$=\frac{165\times {10}^3}{550}$
$=300K$
$\Delta S=\frac{\Delta H}{T}$
$\therefore T=\frac{\Delta H}{\Delta S}$
$=\frac{165\times {10}^3}{550}$
$=300K$