Q. 10

# The ratio C_{P}/C_{V} for gas is 1.29. What is the degree of freedom of the molecules of this gas?

Answer :

**Given:**

= 1.29

**Formula used:**

… (i),

where

γ = ratio of molar heat capacities at constant pressure to constant volume

f = number of degrees of freedom

(i) becomes :

=> … (ii)

Substituting γ = 1.29 in (ii), we get

f = = 6.89 which is approximately equal to 7.

Thus, the number of degrees of freedom is approximately equal to 7.

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