Question

`DeltaH_(comb)^(@)` of carbon is `-x kJ mol^(-1)`. The standard formation of enthalpy of `CO_(2)(g)` will be
A. `-xKJmol^(-1)`
B. `+xKJmol^(-1)`
C. `-x//3KJmol^(-1)`
D. Data is insufficient to predict it

Answer 1

Correct Answer - B
`C(s) + O_(2) (g) rarr CO_(2)(g)`
`Delta H_("comb")^(@) = -x kJ//mol`
`-x = DeltaH^(@) (O_(2)) - (0 + 0)`
`DeltaH^(@) (O_(2)) = -x kJ//mol`