Four cylinders hold equal numbers of moles of argon, hydrogen, nitrogen, and carbon dioxide at the same temperature. The energy is minimum in

Step-by-step solution

The internal energy of an ideal gas is given by U = f 2 nRT , where f is the number of degrees of freedom. Since the number of moles n and temperature T are the same for all four gases, the internal energy is directly proportional to the degrees of freedom f . For argon (monoatomic gas), f = 3 . For hydrogen and nitrogen (diatomic gases), f = 5 . For carbon dioxide (polyatomic gas), f 5 . Since argon has the minimum number of degrees of freedom, its internal energy is the minimum.