For A + B -> P the rate law is rate = k[A][B] with k = 6.0x10^-3 L mol^-1 s^-1. A run uses [A]_0 = 2.0x10^-3 mol L^-1 and [B]_0 = 0.50 mol L^-1. Using ln 2 = 0.693, the half-life of A is

JEE Main levelSingle correct optionDifficulty 2 of 3ck069

For $A + B P$ the rate law is rate = $k [A] [B]$ with $k = 6.0 \times 1 0^{- 3} L mo l^{- 1} s^{- 1}$ . A run uses $[A]_{0} = 2.0 \times 1 0^{- 3} mol L^{- 1}$ and $[B]_{0} = 0.50 mol L^{- 1}$ . Using $ln 2 = 0.693$ , the half-life of $A$ is

B

is in large excess, so

[B] \approx 0.50

M and rate

= k^{'} [A]

with

k^{'} = k [B]_{0} = 6.0 \times 1 0^{- 3} \times 0.50 = 0.0030 s^{- 1}

. Then

t_{1/2} = 0.693/ k^{'} = 231 s