question_answer 1)

Two litres of an ideal gas at 10 atm expands isothermally against a constant external pressure of 1 atm to a volume of 10 litres. How much heat is absorbed and how much work is done by the gas?

Answer:

\[w={{P}_{ext}}\Delta V\] (It is irreversible work) \[=1\times 8=8litre-atm\] \[=8\times 101.3J\] \[{{w}_{\exp }}=-8\times 101.3J\] \[=-810.4J\] \[q={{w}_{\exp }}=810.4J\]