A mixture of one mole of monoatomic gas and one mole of a diatomic gas (rigid) are kept at room temperature $\left(27^{\circ} \mathrm{C}\right)$. The ratio of specific heat of gases at constant volume respectively is:

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · Heat & Thermodynamics

A mixture of one mole of monoatomic gas and one mole of a diatomic gas (rigid) are kept at room temperature

(2 7^{\circ} C)

. The ratio of specific heat of gases at constant volume respectively is:

(A) $\frac{7}{5}$
(B) $\frac{3}{2}$
(C) $\frac{3}{5}$ ✓ Correct
(D) $\frac{5}{3}$

Answer: (C)

Solution

C_{v} = \frac{f}{2} R

. Monatomic

f = 3 \Rightarrow C_{v} = \frac{3}{2} R

; rigid diatomic

f = 5 \Rightarrow C_{v} = \frac{5}{2} R

\frac{( C _{v} ) _{m o n o}}{( C _{v} ) _{d ia}} = \frac{3/2}{5/2} = \frac{3}{5}

Option (C).

JEE Main · 2024 · 08 Apr 2024 · Shift 1 · Single correct option

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