CLEP Chemistry: States of Matter

The states of matter are distinguished by the differences in their bulk properties. The liquid state adapts to the shape of its container but varies only slightly in volume. The solid state maintains a fixed volume and shape, while the gaseous state expands to occupy the volume and shape of its container. Scientists have performed many experiments to understand the common behaviours of gases. They have observed that the state of gas depends on four variables: pressure (P), volume (V), temperature (T), and amount (in moles). The relationships between these variables are known as the gas laws. This free chemistry course on states of matter discusses Boyle’s law, Charles’s law, Gay-Lussac’s law, Avogadro's law and Dalton’s law of partial pressure. It explores the properties of gases, the conditions of the increment of gas pressure as well as the variables that affect it. You will learn about the assumptions of the ideal gas law described by kinetic molecular theory.

Most of the properties of a liquid are the direct result of intermolecular forces, a type of attraction that exists between liquid molecules. Most types are identical to bonding between atoms in a single molecule. This course covers in detail the three most common types of intermolecular forces. To understand them, we must first define what a ‘dipole’ is. This course compares intermolecular forces and thermal energy. It describes boiling point, the heat of evaporation, viscosity as well as surface tension as the physical properties of the liquid. You will learn about the general properties of ionic, molecular and metallic solids. Solids, liquids, and gases can be converted from one phase to another by changing the temperature and pressure. The phase changes are represented by phase curves or phase diagrams. This course defines a phase diagram and illustrates the phase diagram of water and the changes to its physical state when the temperature and pressure vary.

Furthermore, solutions are classified as homogeneous mixtures, which implies that the mixture is a single-phase where the properties will be the same no matter where a sample is taken. It can be confirmed that a mixture of more than one component is a solution most times by merely looking at our mixture. The course states the rule which determines whether two liquids dissolve to form a homogenous solution. The sections that follow discuss Henry's law and consider the process of dissolving sodium chloride (NaCl) in water. It explains the three major types of solutions and the effect of temperature on solubility. You will also learn how to solve for molarity in a given chemical equation. The learning content of this course is crucial for chemistry or anyone with an interest in understanding the states of matter.