One mole of ideal monoatomic gas `(gamma=5//3)` is mixed with one mole of diatomic gas `(gamma=7//5)`. What is `gamma` for the mixture? `gamma` Denotes the ratio of specific heat at constant pressure, to that at constant volume

Options

A. `3//2`
B. `23//15`
C. `35//23`
D. `4//3`

Answer

B

Explanation

Monoatomic `" "` `n_(1) = 1`
Diatomic `n_(2) = 1 gamma_(2) = (7)/(5)`
`(n_(1) + n_(2))/(gamma_("mix") - 1) = (n_(1))/(gamma_(1) - 1) + (n_(2))/(gamma_(2) - 1) implies gamma_("mix") = (3)/(2)`