On combustion carbon forms two oxides CO and `CO_(2)` heat of formation of `CO_(2)` is ` - 94.3` kcal and that CO is `- 26.0` kcal. Heat of combustion of carbon is .

Options

A. `26.0` Kcal
B. `-68.3` kcal
C. `-94.3 Kcal`
D. `-120.3` Kcal

Answer

C

Explanation

`DeltaH_("combustion")("Carbon") C_(s) + O_(2(g)) to CO_(2(g))`
`DeltaH_("formation")(CO),C_((s)) + 1//2O_(2(g)) to CO_((g)) ,DeltaH = - 26KCal`
`DeltaH_("formation")(CO_(2)),C_((s)) + O_(2(g)) to CO_(2(g)) ,DeltaH = - 94.3KCal`
`DeltaH_("formation") (CO_(2)) = DeltaH_("combustion")(CO_(2)) = - 94.3 KCal`