Question 427: Thermodynamics & KTG

Question

Consider two ideal diatomic gases A and B at
some temperature T. Molecules of the gas A are
rigid, and have a mass m. Molecules of the gas
B have an additional vibrational mode, and
have a mass $${m \over 4}$$
. The ratio of the specific heats ($$C_V^A$$ and $$C_V^B$$ ) of gas A and B, respectively is :

Accepted Answer

Degree of freedom of a diatomic molecule if
vibration is absent = 5
Degree of freedom of a diatomic molecule if
vibration is present = 7
$$ 	herefore $$ $$C_V^A$$ = $${5 \over 2}R$$
and $$C_V^B$$ = $${7 \over 2}R$$
$$ 	herefore $$ $${{C_V^A} \over {C_V^B}} = {5 \over 7}$$

Answer

7 : 9

Answer

5 : 7

Answer

3 : 5

Answer

5 : 9

Thermodynamics & KTG

Consider two ideal diatomic gases A and B at some temperature T. Molecules of the gas A are rigid, and have a mass m. Molecules of the gas B have an additional vibrational mode, and have a mass ${m \over 4} . The ratio of the specific heats (C_V^A and C_V^B$ ) of gas A and B, respectively is :

Choose the correct answer: