The activation energy for the forward reaction `X rarr Y` is `60 kJ mol^(-1)` and `Delta H` is `-20 kJ mol^(-1)`. The activation energy for the reverse reaction is

Options

A. `40 kJ mol^(-1)`
B. `60 kJ mol^(-1)`
C. `80 kJ mol^(-1)`
D. `20 kJ mol^(-1)`

Answer

C

Explanation

`E_(a) = E_(a(f)) + Delta H`.
`= 60 + 20 = 80 kJ mol^(-1)`
Note: `Delta H = -ve` means exothermic reaction, so only magnitude value is taken.