Q 11-12-060JEE MainJEE Main 2024 (31 Jan, Shift 2)Easy
A gas mixture consists of 8 moles of argon and 6 moles of oxygen at temperature $T$. Neglecting all vibrational modes, the total internal energy of the system is
Answer: (C) $27RT$
Argon (monatomic, 3 degrees of freedom): $8\times\tfrac32RT = 12RT$.
Oxygen (diatomic, 5 degrees of freedom): $6\times\tfrac52RT = 15RT$.
Total $= 27RT$.
Solution by Sreeraj P, M.Sc Physics