At high temperature, there's presence of only oxygen and nitrogen molecules in the air.

Correct Answer : Option (D) :   Dissociative – recombination reaction of nitrogen and oxygen

Explanation : The reaction taking place below 9000 K for the formation of nitric oxide are dissociation reaction and bimolecular exchange reaction also known as shuffle reaction. They are as follows:

           O2 + M ? 2O + M
           N2 + M ? 2N + M
           NO + M ? N + O + M
           O2 + N ? NO + O

Correct Answer : Option (D) :   Number of transitions per particle per second

Explanation : The collision frequency (Z) when multiplied with the transition probability (Pi, i + 1) yield the number of transitions per particle per second. Since the collision frequency is the number of collisions taking place per particle and the transition probability gives the number of transitions taking place per collision per particle.

Correct Answer : Option (C) :   Less than 1

Explanation : Transition probability is the probability that a molecule will jump to another i + 1 level after the molecular collision. The transition of the molecule moving to a higher energy level requires several number of collisions. This probability value is always less than 1.