During an isothermal process,5.0 J of heat is removed from an ideal gas.What is the change in internal (thermal)energy of the gas?
A)0 J
B)2.5 J
C)5.0 J
D)10 J

Question

Quizplus · Accepted Answer

During an isothermal process, the internal energy of an ideal gas remains constant. Therefore, the change in internal energy (∆U) is zero. The heat removed from the gas is used to do work on the surroundings. The equation for work done in an isothermal process is W = nRT ln(V2/V1), where n is the number of moles of gas, R is the gas constant, T is the temperature, V1 is the initial volume, and V2 is the final volume. Since the internal energy does not change (∆U = 0), all the heat that is removed from the gas is used to do work on the surroundings. Therefore, W = Q = 5.0 J, and ∆U = 0 J.

During an Isothermal Process,5