Water molecules are arranged in a regular ordered way in an ice crystal.
Free expansion of an insulated ideal gas. In (c) the free-expansion process does not pass through equilibrium states from a to b. However, the entropy change S b – S a can be calculated by using the isothermal path shown or any reversible path from a to b.
(a) A reversible cyclic process for an ideal gas, shown as a red closed path. (b) The path can be approximated by a series of long thin Carnot cycles. The entropy change is zero for each Carnot cycle and for the actual cyclic process. (c) The entropy change S b – S a is the same for all paths connecting points a and b.
All possible microscopic states for 4 coins. There can be several microscopic states for each macroscopic state.
In a free expansion of N molecules in which the volume doubles, the number of possible microscopic states increases by 2 N
A passive solar collecting panel for home water heating.
A heat engine takes 0.350 mol of a diatomic ideal gas around the cycle.