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

Learners use the coefficients in a balanced equation to develop the mole ratios of reactants and products involved in the reaction. Five interactive examples illustrate the method, and students test their knowledge by working four problems.

In this interactive object, learners use the ideal gas law to solve a practice problem.

In this learning activity you'll describe the operation of an AND gate by using a truth table, a waveform diagram, a Boolean Algebra equation, a switch analogy, and a written definition.

In this learning activity you'll review how an OR gate operates using a truth table, a Boolean Algebra equation, a switch analogy, and a written statement.

This interactive activity represents the grid modeling technique, a heuristic model for choosing a centralized location for a manufacturing or distribution center within a supply chain network. The formula calculates a central point between the suppliers and the markets. This object requires the latest version of Flash Player.

After a brief review, the student solves five practical shop problems using right angle trigonometry.

In this learning activity you'll practice calculating quadratic equations using the 'completing the square' method.