Liquids, Solids, and Phase Changes

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Liquids, Solids, and Phase Changes

These skills are usually tested on the SAT Subject Test in Chemistry. You
should be able to...

Explain, using a graph, the distribution of the kinetic energy of

molecules of a liquid at different temperatures.

Describe the states of matter and what occurs when a substance

changes state.

Define critical temperature and pressure.

Analyze a phase diagram and the triple point.

Solve water calorimetry problems that include changes of state.

Explain the polarity of the water molecule and hydrogen bonding.

Solve solubility problems, concentration problems, and changes in

boiling point/freezing point of water problems.

Describe the continuum of water mixtures including solutions,

colloids, and suspensions.

This chapter will review and strengthen these skills. Be sure to do the
Practice Exercises at the end of the chapter.

Liquids and solids each have their own properties, including intermolecular

interactions, surface tension, and more. In fact, one very important compound—
water—has distinct properties necessary for life to exist on this planet.

LIQUIDS

Importance of Intermolecular Interaction

A liquid can be described as a form of matter that has a definite volume and takes
the shape of its container. In a liquid, the volume of the molecules and the
intermolecular forces between them are much more important than in a gas. When
you consider that in a gas the molecules constitute far less than 1% of the total
volume, while in the liquid state the molecules constitute 70% of the total volume,