Two liters of `N_(2)` at `0^(@)C` and `5` atm pressure is expanded isothermally against a constant external pressure of `1` atm untill the pressure of gas reaches `1` atm. Assuming gas to be ideal, claculate the work of expansion.

Options

A. `-504.2` joule
B. `-405.2` joule
C. `+810.4` joule
D. `-810.4` joule

Answer

D

Explanation

At constant temperature according to Boyle's law
`P_(1)V_(1)=P_(2)V_(2)`
`5xx2=1xxV_(2)`
`therefore` final volume of gas `V_(2)=10` litre
`W=-P(V_(2)-V_(1))xx101.3 J`
`=-1xx(10-2)xx101.3 J`
`W=-810.4 J`