Question

Four cylinders contain equal number of moles of argon, hydrogen, nitrogen and carbon dioxide at the same temperature. The energy is minimum in
(a) argon
(b) hydrogen
(c) nitrogen
(d) carbon dioxide

Answer 1

a) argon is the correct answer

Answer 2

If four cylinders contain an equal number of moles of argon, hydrogen, nitrogen and carbon dioxide at the same temperature, the argon has minimum energy.  

Explanation:

• This is because, argon is mono atomic whereas hydrogen and nitrogen are diatomic and carbon dioxide is tri-atomic in nature.
• Here, the gases have different values of  $C_v$ ranging from minimum for mono atomic to maximum for tri atomic.
• Also, the energy of a gas is measured in $C_v T$. Hence the argon has minimum level of energy.