For a reaction 2 A+B arrow P, when concentration of B alone is doubled, t1 / 2 does not change and when concentrations of both A and B is doubled, rate increases by a factor of 4 . The unit of rate constant is,

Question

For a reaction 2 A+B arrow P, when concentration of B alone is doubled, t1 / 2 does not change and when concentrations of both A and B is doubled, rate increases by a factor of 4 . The unit of rate constant is, (A) s -1 (B) L mol -1 s -1 (C) mol L -1 s -1 (D) L 2 mol -2 s -1

Tardigrade Admin · Accepted Answer

Rate law: r=k[A]α[B]β, B follows first order kinetics. ∴ β=1 (r2/r1)=([2 A]α[2 B]β/[A]α[B]β) or, 4=2α+β or, α+β=2 or, α=1 ∴ overall order of reaction =2 Hence unit of rate constant = L. mol -1 .S -1

Q. For a reaction $2 A + B \to P$ , when concentration of $B$ alone is doubled, $t_{1/2}$ does not change and when concentrations of both $A$ and $B$ is doubled, rate increases by a factor of $4$ . The unit of rate constant is,

$s^{- 1}$

$L m o l^{- 1} s^{- 1}$

$m o l L^{- 1} s^{- 1}$

$L^{2} m o l^{- 2} s^{- 1}$

Q. For a reaction 2A+B→P, when concentration of B alone is doubled, t1/2​ does not change and when concentrations of both A and B is doubled, rate increases by a factor of 4 . The unit of rate constant is,

s−1

Lmol−1s−1

molL−1s−1

L2mol−2s−1

Rate law: r=k[A]α[B]β,Bfollows first order kinetics. ∴β=1 r1​r2​​=[A]α[B]β[2A]α[2B]β​ or, 4=2α+β or, α+β=2 or, α=1 ∴ overall order of reaction =2 Hence unit of rate constant =L.mol−1.S−1

Q. For a reaction $2 A + B \to P$ , when concentration of $B$ alone is doubled, $t_{1/2}$ does not change and when concentrations of both $A$ and $B$ is doubled, rate increases by a factor of $4$ . The unit of rate constant is,

$s^{- 1}$

$L m o l^{- 1} s^{- 1}$

$m o l L^{- 1} s^{- 1}$

$L^{2} m o l^{- 2} s^{- 1}$