Question

A reaction involving $A, B$ and $C$ as reactants is found to obey the rate law, rate $=k[A]^{x}[B]^{y}[C]^{z} .$ When the concentrations of $A, B$ and $C$ are doubled separately, the rate is also found to increase two, zero and four times respectively. The overall order of the reaction is

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

Answer: (C)

$\because$ On doubling the concentration of $A$,
the rate of reaction becomes two times.
$\therefore $ The order of reaction w.r.t. $A$ is $1$ .
$\because$ On doubling the concentration of $B$,
the rate of reaction does not change.
$\therefore $ The order of reaction with respect to $B$ is $0$ .
$\because$ On doubling the concentration of $C$,
the rate of reaction becomes four times.
$\therefore $ The order of reaction with respect to $C$ is $2$ .
$\therefore $ The overall order of reaction $ = 1 + 0 + 2 =3$