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 $=1+0+2=3$