Question

For the reaction $X_2{O}_{4\left(l\right)}\to 2X{O}_2\left(g\right)$ at 298 K, given the values $\Delta U=9$ kJ and $\Delta S=84J{K}^{–1},\Delta G$ is

• A. -11.08 kJ
• B. +11.08 kJ
• C. -13.55 kJ
• D. +13.55 kJ

Answer 1

The correct option is A -11.08 kJ

$\Delta n_g=2$
$\Delta H=\Delta U+\Delta n_{g}RT$
$\Delta H=9000+\left(2\right)\left(8.314\right)\left(298\right)$
=13955.14
$\Delta G=\Delta -T\Delta S$
=13955.14-(298)(84)
=-11076.8J=-11.076KJ