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Question
The pressure p and volume V of an ideal gas both increase in a process.
(a) Such a process is not possible.
(b) The work done by the system is positive.
(c) The temperature of the system must increase.
(d) Heat supplied to the gas is equal to the change in internal energy.
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Solution
(b) The work done by the system is positive.
(c) The temperature of the system must increase.
Work done by the system depends on the change in volume during the process (ΔW = pΔV), where p be the pressure and ΔV be the change in volume of the ideal gas. Since in this process the volume is continuously increasing, the work done by the system will be positive.
According to the ideal gas equation, `pV = nRT.`
Since both p and V are increasing, temperature (T ) must also increase.
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