Question

$H_2$ reacts much faster with $C{l}_2$ then $D_2$, because:

• A. rate of diffusion of $H_2$ is greater than $D_2$
• B. $H_2$ has lower energy of activation than $D_2$
• C. both (A) and (B) are correct
• D. none of the above is correct

Answer 1

The correct option is B $H_2$ has lower energy of activation than $D_2$

$H_2$ reacts much faster with $C{l}_2$ than $D_2$, because $H_2$ has lower energy of activation than $D_2$. This slowing of the reaction with the heavier isotope is called the deuterium isotope effect.