A+2B arrow C , the rate equation for the reaction is given as Rate =k[. A ].[. B ]. If the concentration of A is kept the same but that of B is doubled what will happen to the rate itself?

Question

A+2B arrow C , the rate equation for the reaction is given as Rate =k[. A ].[. B ]. If the concentration of A is kept the same but that of B is doubled what will happen to the rate itself? (A) Doubled (B) Halved (C) The same (D) Quadrupled

Tardigrade Admin · Accepted Answer

The order of the overall reaction is 2. Rate =k[.A].[.B].=R R'=k[.A].[.2B]. (R/R')=(k [. A ]. [. B ]./k [. A ]. [. 2 B ].)=(k [. A ]. [. B ]./2 k [. A ]. [. B ].) ⇒ 2R=R' i.e, rate become doubles.

Q. $A + 2 B \to C$ , the rate equation for the reaction is given as
Rate $= k [A] [B]$
If the concentration of A is kept the same but that of B is doubled what will happen to the rate itself?

Doubled

Halved

The same

Quadrupled

The order of the overall reaction is 2.
Rate $= k [A] [B] = R$
$R^{^{'}} = k [A] [2 B]$
$\frac{R}{R ^{^{'}}} = \frac{k [ A ] [ B ]}{k [ A ] [ 2 B ]} = \frac{k [ A ] [ B ]}{2 k [ A ] [ B ]}$
$\Rightarrow 2 R = R^{^{'}}$ i.e, rate become doubles.

Q. A+2B→C , the rate equation for the reaction is given as Rate =k[A][B] If the concentration of A is kept the same but that of B is doubled what will happen to the rate itself?