Given the following data
`{:("Substance",DeltaH^(@)(KJ//mol),S^(@)(J//mol K),DeltaG^(@)(kJ//mol),),(FeO(s),-266.3,57.49,-245.12,),(C("Graphite"),0,5.74,0,),(Fe(s),0,5.74,0,),(CO(g),-110.5,197.6,-137.15,):}`
Determine at what temperature the following reaction is spontaneous?
`FeO(s)+C("Graphite")rarrFe(s)+CO(g)`

Options

A. `298 K`
B. `668 K`
C. `966 K`
D. `Delta G^(@)` is `+ve` hence the reaction will never be spontaneous

Answer

C

Explanation

(1)`Delta H=0+[-110.5]-(-266.3)`
`= -110.5+266.3`
`= +155.8 KJ//"mole"`
(2) `Delta S= 27.28+197.6-57.49-5.74=161.65 J//"mole"`
(3) `Delta G=Delta H-T Delta S=0 =155.8-Txx161.65xx10^(-3)`
`Txx161.65xx10^(-3)=155.8 rArr T=963.8K`