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A cylinder contains $$16g$$ of $$O_2$$. The work done when the gas is compressed to $$75\%$$ of the original volume at constant temperature of $$27^\circ$$ is ________.

Discussion:

Given mass of $$O_2$$, m=$$16g$$

Number of moles of $$O_2$$, $$n=\frac{m}{M}$$ where $$M$$=molecular weight of $$O_2$$=$$32g$$
$$n=\frac{16}{32}=\frac{1}{2}$$

Temperature $$T=27^\circ=300K$$

If $$V_1$$ be the original volume and $$V_2$$ be the final volume

Work done by the gas in the isothermal process $$W_0=nRTlog(V_2/V_1)$$$$=0.5*8.31*ln(3/4)$$$$=150*8.31*ln(3/4)$$$$=-358.56J$$