5.6 liter of helium gas at STP is adiabatically compressed to 0.7 liter. Taking the initial temperature to be `T_1,` the work done in the process is

Options

A. `(9)/(8)RT_(1)`
B. `(3)/(2)RT_(1)`
C. `(15)/(8)RT_(1)`
D. `(9)/(2)RT_(1)`

Answer

A

Explanation

`W=(nR(T_(1)-T_(2)))/(r-1) T_(1) (5.6)^(2//3)=T_(2)(0.7)^(2//3)`
`impliesT_(2)=T_(1)(8)^(2//3)`
`=T_(1)xx4 W =(nRxx3T_(1))/(2//3)=(9)/(2) nRT_(1)`
But `n =(1)/(4) implies W = (9)/(8)RT_(1)`.