The molar specific heat at constant pressure of an ideal gas is `(7//2 R)`. The ratio of specific heat at constant pressure to that at constant volume is

Options

A. `9//7`
B. `7//5`
C. `5//7`
D. `8//7`

Answer

B

Explanation

`C_(P) = 7/2 R`
`C_(upsilon) = C_(p)-R = 7/2 R-R = 5/2 R`
`gamma = (C_p)/(C_(upsilon)) = (7//2R)/(5//2 R) = 7/5`.