Question

When the concentration of reactants in the reaction $A$$\to$$B$ is increased by $8$ times, the rate increases only $2$ times. The order of the reaction is:

• A. $1/3$
• B. $1$
• C. $1/2$
• D. $2$

Answer 1

The correct option is A $1/3$

$A\to B$

$Rate,r=k[A{]}^n$ .... (i)

$When,\left[A\right]\to 8\left[A\right]$$⟹r\to 2r$

$2r=k[8A{]}^n$ .... (ii)

From equation i and ii,

Hence, $2=8^n$

$n=\frac{1}{3}$

Option A is correct.