Students use algebra to rearrange formulas and solve for the missing volume, density, or mass quantity.

Learners read about lab equipment and basic safety measures. In a quiz, they view photos and determine if the lab technicians pictured are using safe practices.

Students practice identifying common elements from the periodic table by name or symbol.

In this screencast, students read about the basic organization and structure of the periodic table of elements. Students identify elements as belonging to a group, a period, or neither.

In this screencast we are introduced to the lab equipment used to contain and dispense chemicals.

Students read brief descriptions of atoms, molecules, elements, and compounds, and complete a matching exercise that pictures these particles and molecules as pieces of taffy.

In this interactive lesson, students examine the quantitative relationship between chemicals in a balanced mathematical equation.

In this animated object, learners examine the chemistry behind table salt.

In this interactive object, learners examine how to properly dilute hydrochloric acid.

In this interactive object, learners calculate the amount of heat evolved or absorbed in chemical reactions. Four practice problems are provided.

Learners examine how chemists use moles to "count" atoms by weight. Examples are given.

Learners complete an exercise to match chemical formulas with the names of binary compounds, tertiary compounds, and ions.

Learners read definitions of atomic symbols, atomic numbers, and mass numbers and then answer questions about the number of neutrons, protons, and electrons in select elements.

In this screencast, learners examine the kinds of physical and chemical changes that occur in substances.

Learners examine how melting, vaporization, and sublimation require energy input while freezing and condensation release energy.

Vapor pressure is the pressure exerted by molecules in the gas phase in equilibrium with a liquid or a solid. Two examples are used to illustrate vapor pressure: the drying of clothes and the evaporation of ice.

In this animated object, students examine what happens when electrons share molecules.

Learners examine a table of common polyatomic ions. Eight examples are provided for practice.

Learners assign oxidation numbers to atoms in neutral compounds and in polyatomic ions. Six examples are worked through in detail, and three problems are provided.

In this interactive object, students examine a type of chemical bond known as the "hydrogen bond."