Question

For the reaction,
${Ag}_{2}O\rightleftharpoons 2Ag\left(s\right)+\frac{1}{2}{O}_2\left(g\right)$
Calculate the temperature at which free energy change is zero. At a temperature lower than this, predict whether the forward of the reverse reaction will be forward. Give reason
($\Delta H=+30.56kJ;\Delta S==+0.066kJ{K}^{-1}{mol}^{-1}$)

Answer 1

We have,

$\Delta G=\Delta H-T\Delta S$

if free energy change is zero then we gave

$0=\Delta H-T\Delta S$

$0=30560-T\ast 66$

$30560=T\ast 66$

we get T = 463 K

at temperature lower than that of 463K, free energy change become positive and reaction goes in backward direction.