Answer:
-7.2 * 10^4 kJ mol-1
Explanation:
First we obtain the change in enthalpy for the reaction;
ΔHrxn= ΔHproducts - ΔHreactants
ΔHrxn=[( −510 ) - (−110.53) + (−277.69)]
ΔHrxn= -121.78 * 3 J mol-1
The we obtain the entropy change of the reaction
ΔSrxn= ΔSproducts - ΔSreactants
ΔSrxn= [(191) - (197.67) + (160.7)]
ΔSrxn= -167.37 J K-1 mol−1
Then we calculate ΔG at 298 K
ΔG = ΔH - TΔS
ΔG = ( -121.78 * 3) - (298) (-167.37)
ΔG = -7.2 * 10^4 kJ mol-1