Assertion (A) : Both `H_(2)(g)+Cl_(2)(g) rarr 2HCl(g)` and `H_(2)(g)+Br_(2)(g) rarr 2HBr(g)` have the same order of reaction.
Reason (R ): Both reaction proceed by the same mechanism.

Options

A. If both `(A)` and `(R )` are correct, and `(R )` is the correct explnation of `(A)`.
B. If both `(A)` and `(R )` are correct, but `(R )` is noth the correct explanation of `(A)`.
C. If `(A)` is correct, but `(R )` is incorrect.
D. If both (A) and (R ) are incorrect.

Answer

D

Explanation

Correct (A) `H_(2)+Cl_(2) rarr 2HCl` is zero order while `H_(2)+Br(2) rarr` is of order `1.5`.
Correct (R ) The two reactions proceed by different mechanism.