Thermal capacity of 40 g of aluminium `(s = 0.2 cal//g - K)` is

Options

A. The molar mass of the gas is `40`g
B. The molar mass of the gas cannot be determined from the data given
C. The number of degrees of freedom of the gas molecules is `6`
D. The number of degrees of freedom of the gas molecules is `8`

Answer

A, C

Explanation

`C_(P)-C_(V) =R, M (0.25 - 0.15) = 2[M`= molar mass]
` implies M = (2)/(0.05) = 40`g
`(C_(P))/(C_(V)) = gamma = (0.2)/(0.15) = (4)/(3) =1 + (2)/(f)`
`implies` f = degrees of freedom = `6`