Question

For hypothetical chemical reaction A $\to$ I, it is found that the reaction is third order in A. What happens to the rate of reaction when the concentration of A is doubled ?

• A. Rate increases by a factor 2.
• B. Rate decreases by a factor 3.
• C. Rate increases by a factor 8.
• D. Rate remains unaffected.

Answer 1

The correct option is C Rate increases by a factor 8.

$r_1=k[A{]}^3$
$r_2=k[2A{]}^3$
Dividing equation (ii) by (i),
$r_2=8r_1$