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

Answer

C

Explanation

`C_P=7/2 R = (1+f/2)R`
f=5
`C_V=(5R)/(2), therefore gamma =(C_P)/(C_V)=7/5`