Rate law for the reaction aA + bB cC + dD is r = k [ A ][ B ] , the rate of reaction doubles if

Step-by-step solution

The rate law is given as r = k[A][B] for the reaction aA + bB cC + dD . The initial rate is r₁ = k[A][B] . To double the rate, we require r₂ = 2r₁ = 2k[A][B] . When concentration A is doubled while B remains constant, the new rate becomes k(2[A])([B]) = 2k[A][B] . This matches the required doubling condition, confirming option B is correct. Other options yield different results: doubling both concentrations quadruples the rate, doubling B while halving A maintains the original rate, and halving B while keeping A co