Given, rate law expression (r)=k[A][B]2 Final volume (V2) is reduced to half of initial volume (V1) i.e. V2=1∕2V1 ∴ Final concentration [A] and [B]=[2A] and 2[B] ∴ Final rale r′=k[A]0[B]2=k[2A][2B]2 r′=k×2×4[A][B]2 ⇒r′=8k[A][B]2 ∴ r′=8r i.e. rate increases by 8 times.