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Question
1.0 mol of a monoatomic ideal gas is expanded from state (1) to state (2) as shown in figure. Calculate the work done for the expansion of gas from state (1) to state (2) at 298 K.
Solution
It is clear from the figure that the process has been carried out in infinite steps, hence it is isothermal reversible expansion.
w = – 2.303 nRT log `V_2/V_1`
But, p1V1 = p2V2
⇒ `V_2/V_1 = p_1/p_2 = 2/1` = 2
∴ w = – 2.303 nRT log `p_1/p_2`
= – 2.303 × 1 mol × 8.314 J mol–1 K–1 × 298 K–1 × log 2
= – 2.303 × 8.314 × 298 × 0.3010 J
= –1717.46 J
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