Question

The first law of thermodynamics D. The cylinder, with the piston still locked in place, is now immersed in a mixture of ice and water and allowed to come to thermal equilibrium with the mixture. The piston is then moved inward very slowly. in such a way that the gas is always in thermal equilibrium with the ice-water mixture. We will refer to this slow compression of the gas as process 3. 1. During process 3, do the following quantities increase, decrease, or remain the same? Explain. • the volume of the gas • the temperature of the gas • the internal energy of the gas • the pressure of the gas 2. Sketch process 3 on the PV diagram provided. 3. Determine whether each of the following quantities is positive, negative, or zero: • the work done on the gas during process 3 (explain your reasoning by referring to a force and a displacement). . the energy transferred thermally to the gas during process 3. 4. Are your answers above consistent with the first law of thermodynamics? Explain. E. How does the compression in process 3 differ from that in process 1? Explain F. A student is considering process 3: "The temperature doesn't change it is an isothermal process. Therefore the ener transferred thermally must be zero. me you agree with this student? Explain.

Answer 1

Question1.

. Since piston is moving inwards ,the volume of the is decreasing.

. The gas is always in thermal equilibrium with ice and water mixture, hence i'ts temperature is constant.

. The internal energy of an ideal gas is proportional to it's absolute temperature, since temperature remains constant internatl energy remains constant.

Using ideal gas equation pV = nRT

p = nRT/V, since temperature is constant pressure will increase.