Question

The order of elementary reactions can be determined by the number of molecules participating in a collision.
Based on this knowledge, which of the following is least likely an elementary reaction?

• A. A unimolecular process such as $C{H}_{3}NC\to C{H}_{3}CN$
• B. A bimolecular reaction such as $NO+O_3\to N{O}_2+O_2$
• C. A tirmolecular process such as $O+N_{2}O+N\to N{O}_2+N_2$
• D. A tetramolecular process such as $N_2+2H_2+C{l}_2\to 2N{H}_{4}Cl$

Answer 1

The correct option is A A unimolecular process such as $C{H}_{3}NC\to C{H}_{3}CN$

A chemical reaction involving one or more chemical species reacting to form products in a single reaction step & a single transition state is known as an elementary reaction.

From the given options, only uni molecular process (i.e.(A)) is least likely to be an elementary reaction.