When 0.1 mol of a gas absorbs `41.75 J` of heat at constant volume, the rise in temperature occurs equal to `20^(@)C`. The gas must be

Options

A. triatomic
B. diatomic
C. polyatomic
D. monoatomic

Answer

B

Explanation

`C_(v) ` ( heat absorbedper degree rise per mole)
`=( 41.75J)/( 0.1 mol xx 20^(@)) = 20.875 JK^(-1) mol^(-1)`
`C_(p) = C_(v) + R = 20.875 + 8.314 JK^(-1) mol^(-1)`
`= 29.189 JK^(-1) mol^(-1)`
`(C_(p))/( C_(v)) = ( 29.189)/( 20.875) = 1.40`. Hence, the gas is diatomic.