Which of following equations does not correspond to the standard enthalpy of atomization?

Options

A. `H_(2) (g) rarr 2 H (g)`
B. `CH_(4) (g) rarr C (g) + 4 H (g)`
C. `Na (s) rarr Na (g)`
D. `Br_(2) (g) rarr 2Br (g)`

Answer

D

Explanation

`Delta_(a) H^(@)` is the enthalpy change when one mole of the substance in its stantard state dissociates into isolated atoms in the gas phase. The standard state of bromine is `Br_(2)` (liquid). In case of `H_(2) (g)`,k the enthalpy of atomization is the same as bond dissociation enthalpy. In `CH_(4) (g)`, it is just the enthalpy of atomization.