Lesson 2: Solids & Liquids - Molecules (& Atoms & Ions) in Restricted Motion
In this lesson we will study the condensed phases of matter - the solid and the liquid phases.
In the gas phase the attraction between particles of gas is negligible - in fact, we assumed that it was zero. But in the condensed phases, those attractive forces are important, they bind the molecules (or atoms) together in the liquid and solid phases. Therefore, one of the things we will look at is the nature - and especially the relative strength - of the intermolecular bonds in solids and liquids and try to relate their strength to some of the common properties: melting point, boiling point, surface tension, vapor pressure, and so on.
We will also learn to calculate the amount of energy that is needed to heat (or that is released on cooling) a solid or a liquid as well as the amount of energy involved in changing from a solid to a liquid and from a liquid to a gas. As you might suspect, the amount energy involved also depends on how strongly the particles are bound together as well as on how much of the material is involved.
The lab exercise for this lesson involves measuring the amount of heat required to change the temperature of a sample of a metal.
Be sure to review the objectives for this lesson as you are working through it. There is also a lab report and a problem set to turn in.
When you have completed the lesson, take the Self Quiz in your workbook and check your answers by going to the