Question

Question #20ae1

Answer 1

To answer any `Delta(X)_(rxn)` problem; where `X=H^0,S^0, or G^0` we can always use Hess's Law.

Hess's Law:
`Delta(G^0)_(rxn)=(Sum DeltaG (Products))-(Sum DeltaG(Reactants))`

For our reaction `2CO(g)+O_2(g)->2CO_2(g)`

Notice: You cannot omit the physical state for these problems, this is why I added the (g) and I'm going to assume (g) for all.

`Delta(G^0)_(rxn)=[(2mol CO_2g*-394.4 (kJ)/(mol))] -[(2mol COg*-137.3(kJ)/(mol))+(1mol O_2g*0(kJ)/(mol))]`

Notice: the mol units cancel out leaving our answer in kJ.

`Delta(G^0)_(rxn)=[-788.8kJ]-[-274.6kJ]`

`Delta(G^0)_(rxn)=-514.2kJ`