question_answer 85)

  An ideal gas is allowed to expand against a constant pressure of 2 bar from 10 L to 50 L in one step. Calculate the amount of work done by the gas. If the same expansion were carried out reversibly, will the work done be higher or lower than the earlier case? (Given : 1 L bar = 100 J)

Answer:

  \[w=P\Delta V\] \[=2\times 40=80L\,bar\] \[=80\times 100J\] \[=8kJ\] \[{{w}_{\exp }}=-8kJ\](work done by the gas) \[{{w}_{rev.}}>{{w}_{irr.}}\]