A heating coil is immersed in a 100 g sample of `H_(2)O` (l) at a 1 atm and `100^(@)` C in a closed vessel. In this heating process , `60%` of the liquid is converted to the gaseous form at constant pressure of 1 atm . The densities of liquid and gas under these conditions are 1000 `kg//m^(3)` and 0.60 `kg//m^(3)` respectively . Magnitude of the work done forthe process is :
(Take : 1L-atm= 100J)`

Options

A. 4997J
B. 4970J
C. 9994 J
D. None of these

Answer

C

Explanation

`w=-P_(ext)(V_(f)-V_(i))`
`=-10^(5)((60xx10^(-3))/(0.60)+(40xx10^(-3))/(1000)-(100xx10^(-3))/(1000))`
`=-10^(5)(100xx10^(-3)+0.04xx10^(-3)-0.1xx10^(-3))`
`|w|=9994J`