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

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.

Learners view several movie clips that demonstrate the use of an indicator to follow the neutralization reaction that occurs when an acid and a base are mixed. Students test their knowledge in a series of questions. Immediate feedback is given.

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

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

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.

Learners read the definition of atomic weight and obtain the weights of elements by viewing the Periodic Table and charts that list atomic weights by name or symbol.

In this animated activity, learners examine the terms "half-reaction," "oxidizing agent," and "reducing agent" and follow five interactive examples to balance equations for oxidation-reduction reactions. Three problems are provided as a self-check.

Learners read a brief introduction to monosaccharides, disaccharides, and polysaccharides. The processes for dehydration synthesis and hydrolysis are shown.

Viewers watch an introduction to monosaccharides, disaccharides, and polysaccharides. The processes for dehydration synthesis and hydrolysis.

Learners examine how the boiling point increases with increasing pressure. An example from industry is given.

In this interactive object, the learner examines how pressure and volume relate to each other.

In this interactive object, learners calculate formula and molecular weights by working through five examples and two problems.

Learners calculate gas density from the standard molar volume and observe how the density increases with the increasing molecular weight of the gas.

Learners examine the method for calculating the atomic weight of copper from the natural percent composition of each of its two isotopes.

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

In this interactive object, students examine how the volume and temperature of an ideal gas relate under conditions of constant pressure and quantity.

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

Learners identify combination, decomposition, displacement, and combustion types of redox reactions. They also watch a video clip that demonstrates the reaction of sodium and water.

Learners view an animated presentation showing how the pH level of a cleaning solution is controlled in a closed-loop system in a manufacturing setting. A quiz completes the activity.

Atomic weights are used to convert the mass of a sample into the number of moles of the element in the sample and vice versa. Four examples are provided for practice.

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

Learners follow a four-step process to determine the empirical formula of a compound from the masses of its constituent elements. The molecular formula is determined in a fifth step using the molecular weight of the compound.

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

In this interactive object, learners identify charges on ions, write new formulas based on charge, and balance equations using coefficients.