A reaction is second order with respect to a reactant. If the concentration of that reactant is reduced to half, how does the rate change?

1. Rate $= k[A]^2$. 2. New rate $= k\left(\tfrac{[A]}{2}\right)^2 = \tfrac{1}{4}k[A]^2$. 3. So the rate becomes one-fourth of the original. 4. Distractor A applies a first order dependence by mistake. _Source: NCERT Class 12 Chemistry Ch 3 "Chemical Kinetics", p.24_