Specific heat of a monoatomic gas at constant volume is `315 J kg^(-1) K^(-1)` and at a contant pressure is `525 J kg^(-1) K^(-1)`. Calculate the molar of the gas.

Options

A. `396 g mol^(-1)`
B. `39.6 g mol^(-1)`
C. `500 g mol^(-1)`
D. `50 g mol^(-1)`

Explanation

`C_(p) = M xx 525` and `C_(v) = M xx 315` where M is the molecular mass .
`C_p - C_v = R (R = 8.314 JK^(-1) mol^(-1)) (M xx 525) - (M xx 315) = 8.314`
`M (525 - 315) = 8.314`
`M = (8.314)/(210) = 0.0396 kg mol^(-1) = 39.6 g mol^(-1)`