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

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

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 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.

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

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

Learners view illustrations showing the direct dependence of the volume of a gas on temperature and consider the relationship between the Kelvin and Celsius temperature scales.

Boyle's Law states that gas volume varies inversely with the pressure at constant temperature and is described by the equation PV = constant. An example of a sample of gas at two conditions of P and V is used to illustrate the law.

Learners examine the method used to calculate the mass percent of an element in a compound. Three examples and one problem illustrate the method.

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

In this well-illustrated activity, learners examine the three types of intermolecular forces: dipole-dipole forces, London or Van der Waals forces, and the hydrogen bond. Two interactive questions are included.

Ions are electrically charged particles obtained from an atom or from a chemically bonded group of atoms by adding or removing electrons. Eight examples illustrate the number of protons, neutrons, and electrons in positive ions (cations) and in negative ions (anions).

Learners examine the meaning of theoretical yield, actual yield, and percent yield. They test their knowledge by solving two problems.

In this animated object, students examine the role that the solubility of water plays in various biological functions.

Students read an explanation of chemical formulas in this animated activity. A quiz completes the object.

Learners examine the meaning of oxidation, reduction, and half-reaction, and watch a film showing the deposition of copper metal from the reduction of copper (II) ion by aluminum. A brief quiz completes the activity.

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

Students read different definitions of "acids" and "bases." In an interactive exercise, they identify if a substance is an acid or a base.