Find `DeltaG^(@)andDeltaH^(@)` for the reaction
`CO(g)+(1)/(2)O_(2)(g) toCO_(2)(g)at 300K`
when the standard entropy is `-0.094kJ mol^(_1)K^(-1).` The standard Gibbs free energiers fo formation for `CO_(2)andCOare-394.4 and-137.2kJ mol^(-1) respectively.`

Explanation

`DeltaG = -394.4-(-137.2)=-257.2 kJ mol^(-1)`
`DeltaG < 0" "` so, reaction is spontaneous
`DeltaG = DeltaH - TDeltaS`
`-257.2 = DeltaH - 300 xx(-0.094)`
`DeltaH = -285.4 kJ "mole"^(-1)`
This reaction is exothermic (combustion) and entropy is decreasing so reaction is spontaneous at lower temperature and non-spontaneous at higher temperature.