When an ideal gas undergoes a slow isothermal expansion:
A)the work done by the gas is the same as the energy absorbed as heat
B)the work done by the environment is the same as the energy absorbed as heat
C)the increase in internal energy is the same as the heat absorbed
D)the increase in internal energy is the same as the work done by the gas
E)the increase in internal energy is the same as the work done by the environment

Question

Quizplus · Accepted Answer

During a slow isothermal expansion, the temperature of the gas remains constant. This means that the change in internal energy of the gas is zero. According to the first law of thermodynamics, the change in internal energy of a system is equal to the heat absorbed by the system minus the work done by the system. Since the change in internal energy is zero, the heat absorbed by the system is equal to the work done by the system. Therefore, choice A is correct.

When an Ideal Gas Undergoes a Slow Isothermal Expansion