Question

When an ideal gas undergoes unrestrained expansion, no cooling occurs because of the molecules:

• A. are above the inversion temperature.
• B. exert no attractive forces on each other.
• C. do work equal to loss in kinetic energy.
• D. collide without loss of energy.

Answer 1

The correct option is B exert no attractive forces on each other.

According to postulates of kinetic theory, there is no intermolecular attractions or repulsions between the molecules of ideal gases.
Thus when an ideal gas undergoes unrestrained expansion, no cooling occurs because the molecules do not exert any attractive forces on each other.