You have a block of ice at 0°C. Heat is added to the ice, causing an increase in entropy of 120J/K. How much ice melts into water in this process?

2.0 mol of helium at 280℃ undergo an isobaric process in which the helium entropy increases by 35 J/K. What is the final temperature of the gas?

A thin partition divides a container of volume V into two parts. One side contains nA moles of gas A in a fraction fA of the container; that is, VA = fAV. The other side contains nB moles of a different gas B at the same temperature in a fraction fB of the container. The partition is removed, allowing the gases to mix. Find an expression for the change of entropy. This is called the ,entropy of mixing.

A 2.0 mol sample of oxygen gas in a rigid, 15 L container is slowly cooled from 250℃ to 50℃ by being in thermal contact with a large bath of 50℃ water. What is the entropy change of (a) the gas and (b) the universe?

CALC Two moles of an ideal gas occupy a volume V. The gas expands isothermally and reversibly to a volume 3V. (a) Is the velocity distribution changed by the isothermal expansion? Explain.

CALC You make tea with 0.250 kg of 85.0°C water and let it cool to room temperature 120.0°C2. (a) Calculate the entropy change of the water while it cools.

A 15.0-kg block of ice at 0.0°C melts to liquid water at 0.0°C inside a large room at 20.0°C. Treat the ice and the room as an isolated system, and assume that the room is large enough for its temperature change to be ignored. (a) Is the melting of the ice reversible or irreversible? Explain, using simple physical reasoning without resorting to any equations.