Question

The enthalpy of formation of ammonia is `- 46.2 mol^(-1)`. The enthalpy change for the reaction
`2NH_(3) rarr N_(2) + 3 H_(2)` is
A. `42.0 kJ`
B. `64.0 kJ`
C. `80.0 kJ`
D. `92.0 kJ`

Answer 1

Correct Answer - D
`underset(2"moles")(2NH_(3))toN_(2)+3H_(2)`
The enthalpy of formation of ammonia
`=-46kJ mol^(-1)`
`DeltaH"of given reaction " =-2xx(-46)=92kJ`