| Topic |
Concepts |
Experiment |
| Heating Curve |
The processes that occur when a substance is heated are explained. |
A heating curve is recorded for a substance, which is displayed to illustrated the accompanying phase changes. The viewer is asked to determine the melting point, boiling point, and enthalpies of fusion and vaporization. |
| Vapor Pressure |
The liquid-gas and solid-gas equilibria are examined and the Claussius-Clapeyron is presented. |
The vapor pressure of ethanol is measured at various temperatures. A Classius-Clapeyron plot is prepared, and the viewer is asked to determine the normal boiling point and standard enthalpy and entropy of vaporization for ethanol. |
| Phase Diagram: Part 1 |
The properties of a phase diagram are described. |
The viewer is asked to determine the stable phase at various temperatures and pressures. |
| Phase Diagram: Part 2 |
The effect of crossing a phase line in a phase diagram is discussed. |
A sample is heated isobarically such that the process crosses a phase line in the phase diagram. The viewer is asked to determine the sublimation temperature at the experimental pressure. |
| Phase Diagram: Part 3 |
The effect of crossing a phase line in a phase diagram is discussed. |
A sample is compressed isothermally such that the process crosses a phase line in the phase diagram. The viewer is asked to determine the pressure at which the phase change occurs at the experimental temperature. |
| Phase Diagram: Part 4 |
The triple point is defined and its significance is discussed. |
Temperature or pressure changes are used to drive a substance through the triple point. The viewer is asked to determine the triple-point temperature and pressure. |
| Phase Diagram: Part 5 |
The critical point is defined and its significance is discussed. |
The transition between a liquid and gas is examined via two different routes, one of which crosses a phase line and one of which does not (passing through the super-critical region instead). Colors are used to represent the sample density and illustrate how it is possible to convert a sample from a liquid to a gas (or vice-versa) without producing a phase-change reaction. |
| Phase Diagram |
The features of a phase diagram are described. |
A phase diagram is presented along with a sample confined in a cylinder with a movable barrier. The viewer may alter the temperature and pressure of the sample in order to explore the features of the phase diagram. |
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