Mechanism of a hypothetical reaction X 2 + Y 2 → 2XY is given below ( 1 ) X 2 → X + X (fast) ( 2 ) X + Y 2 ⇌ XY + Y (slow) ( 3 ) X + Y → XY (fast) The overall order of the reaction will be

Step-by-step solution

X 2 → X + X (Fast) X + Y 2 ⇌ X Y + Y (Slow) As we know that slow step is Rate determine step ∴ R a t e = K X [ Y 2 ] (i) From last step K = X 2 X 2 X 2 = K 1 [ X 2 ] (ii) From equation (i)&(ii) Rate = K K 1 X 2 1 2 Y 2 Rate = K ' X 2 1 2 Y 2 Order = 1 2 + 1 = 1.5