a gas mixture consists of 2 moles of oxygen and 4 moles of argon at temp T - Physics - Kinetic Theory

Question

a gas mixture consists of 2 moles of oxygen and 4 moles of argon
at temp T neglecting all vibrational modes , what will be the total
internal energy of the system

Hansraj Rai · Accepted Answer

Oxygen is diatomic and has five degree of the freedom whereas argon being monatomic has only three degrees of freedom.

For a gas,

$U = μ N \times \frac{1}{2} k T = μ \times \frac{1}{2} R T$

N is the degrees of the freedom.

Therefore the total energy,

$U' = 2 \times 5 \times \frac{1}{2} R T + 4 \times 3 \times \frac{1}{2} R T = 11 R T$

a gas mixture consists of 2 moles of oxygen and 4 moles of argon at temp. T . neglecting all vibrational modes , what will be the total internal energy of the system