In this animated and interactive object, learners examine the inverse proportionality of wavelength and frequency and their relationship to the speed of light.

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

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.

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.