Question

Which of these parameters affect the number of collisions?

(a) Pressure of the setup

(b) Kinetic energy between the molecules

(c) Density of the apparatus

(d) Temperature of the apparatus

The question was asked in class test.

This interesting question is from Introduction to Nonequilibrium Systems topic in chapter Properties of High Temperature Gases of Aerodynamics

Answer 1

Right choice is (b) Kinetic energy between the molecules

The explanation is: For a molecule to become vibrationally excited, it has to undergo several number of collisions which is affected by the kinetic energy present between these colliding particles. Higher kinetic energy results in higher gas temperature which eventually leads to lesser number of collisions required for the molecule to become vibrationally excited.