Question

The heat of combustion of carbon is -94 kcal at 1 atm pressure. The intrinsic energy of `CO_(2)` is
A. `+94` kcal
B. `-94` kcal
C. `+47` kcal
D. `-47` kcal

Answer 1

Correct Answer - B
`C_((S))+O_(2)(g)rarrCO_(2(g)), Deltan_(g)=1-1=0`
`therefore DeltaE=DeltaH=-94 kcal`
`DeltaE=E_(CO_(2))-(E_(C)+E_(O_(2)))=E_(CO_(2))-(0+0)`
`or E_(CO_(2))=DeltaE=-94 kcal`.