For the Reaction CuS(s) + H₂(g) $\leftrightharpoons$ H₂S(g) + Cu(s) $\Delta$ G ^$\circ$

Multiple Choice

For the reaction CuS(s) + H₂(g) $\leftrightharpoons$ H₂S(g) + Cu(s) ,
$\Delta$ G ^$\circ$ _f (CuS) = -53.6 kJ/mol
$\Delta$ G ^$\circ$ _f (H₂S) = -33.6 kJ/mol
$\Delta$ H ^$\circ$ _f (CuS) = -53.1 kJ/mol
$\Delta$ H ^$\circ$ _f (H₂S) = -20.6 kJ/mol
Calculate $\Delta$ G at 798 K and 1 atm pressure (assume $\Delta$ S ^$\circ$ and $\Delta$ H ^$\circ$ do not change with temperature) .

A) -1.02 kJ/mol
B) -1.22 kJ/mol
C) -1.42 kJ/mol
D) -1.62 kJ/mol
E) None of the above