Q. For the reaction 2A → products, the rate law is rate = k[A]^2. What is the order of the reaction with respect to A and overall?
✅ Correct Answer: (B)
Second order with respect to A; overall second order
Explanation: The exponent of [A] in the rate law gives the order with respect to A: it's 2, so second order in A. Since there's only A in the rate law, the overall order is also 2. Option 1 is wrong because the exponent is not 1. Option 3 is wrong because zero order would have [A]^0. Option 4 is inconsistent (can't be second in A and overall first).
Explanation by: Sikhar Chaudhary
The exponent of [A] in the rate law gives the order with respect to A: it's 2, so second order in A. Since there's only A in the rate law, the overall order is also 2. Option 1 is wrong because the exponent is not 1. Option 3 is wrong because zero order would have [A]^0. Option 4 is inconsistent (can't be second in A and overall first).