An ideal gas is allowed to expand against a constant pressure of 2 bar from 10 L to 50 L in one stop. Calculate the amount of work done by the gas. If the sameexpansion were carried out reversibly,will the workdone be higher or lower than the earlier case ?

An ideal gas is allowed to expand against a constant pressure of 2 bar

1.	An ideal gas is allowed to expand against a constant pressure of 2 bar from 10 L to 50 L in one stop. Calculate the amount of work done by the gas. If the sameexpansion were carried out reversibly,will the workdone be higher or lower than the earlier case ?
Answer» <P> Solution :In the firstcase, as the expansion is against constant external pressure, ,brgt `w= - P_(ext) (V_(2)-V_(1)0 = - 2 "bar" xx ( 50-10) L= -80 L "bar" = - 80 xx 100 J = - 8 kJ ( 1L `bar` = 100 J) ` If the above expansion were carried out reverisbly, the INTERNAL pressure of the gas should be infinitesimally greater than the external pressure at everystage. Hence, the work DONE will be more.