A piece of ice at 0 °C is placed in an open, insulated beaker located on a laboratory bench where the ambient temperature is 25 °C and the relative humidity is low. Over time the ice melts completely, and the resulting liquid water eventually evaporates until the beaker is dry.
Later, an identical mass of ice is placed in a perfectly sealed, well-insulated container equipped with a movable piston that allows the internal pressure to adjust infinitesimally as temperature is changed. The container is slowly warmed from 0 °C to 25 °C in tiny temperature increments, always allowing the system to come to equilibrium before the next change.
(a) For the open-beaker experiment, evaluate whether the melting of ice is reversible or irreversible under the stated laboratory conditions. Cite specific thermodynamic or kinetic factors in your reasoning.
(b) For the same open-beaker experiment, evaluate whether the subsequent evaporation of liquid water is reversible or irreversible, again providing justification.
(c) Analyze the idealized sealed-container experiment. Discuss whether the combined melting and vaporization processes conducted in this quasi-static manner meet the criteria for reversibility. In your answer comment on entropy production in the system plus surroundings.
(d) Synthesize your observations from parts (a)–(c) to formulate a concise set of conditions that must be satisfied for a physical phase change to be considered reversible. Provide at least two distinct conditions and illustrate each with reference to the scenarios above.