One mole of an ideal monatomic gas undergoes a process in which its temperature doubles and its pressure becomes four times the initial pressure. What is the entropy change for this process?

R * ln(2) / 2
9 * R * ln(2) / 2
2 * R * ln(2)
5 * R * ln(2) / 2

Correct answer: R * ln(2) / 2

Solution

The entropy change formula for an ideal gas lets us use any two state variables. We know the temperature ratio and can find the volume ratio from PV = nRT.

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