Q. The following homogeneous gaseous reactions were experimentally found to be second order overall. 1.$2NO \rightarrow N_{2} + O_{2}$ 2.$3O_{2} \rightarrow 2O_{3}$ 3.$N_{2}O_{3} \rightarrow NO + NO_{2}$ 4. $H_{2} + I_{2} \rightarrow 2HI$ Which of these are most likely to be elementary reaction that occur in one step?
A) 3 only
B) 1 and 3
C) 1 and 4
D) 3 and 4
Explanation
(c)
$2NO \rightarrow N_{2} + O_{2}$
Rate =$k\lbrack NO\rbrack^{2}$
Hence, order of reaction is 2
$H_{2} + I_{2} \rightarrow 2HI$
Rate =$k\left\lbrack H_{2} \right\rbrack\lbrack I_{2}\rbrack$
Hence, order of reaction is (1+1)=2
Therefore these reactions are most likely to be elementary reaction that occurs in one step.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.