Eduprobe
Question:
The gas mixture consists of 3 moles of oxygen and 5 moles of argon at temperature T. Considering only translational and rotational modes, the total internal energy of the system is:
12 RT
20 RT
15 RT
4 RT
Solution:
U=f1/2n1RT+f2/2n2RT=5/2(3RT)+3/2×5RT
U=15RT