In this animated object, students are introduced to moles as a measurement.

Students solve a molarity problem in a drag and drop exercise.

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.

Learners observe that the volume of one mole of any gas is 22.4 L at standard temperature and pressure. An illustration shows that only the mass of the molar volume differs with the identity of the gas.

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.

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 how five or six groups of electrons around a central atom cause the shape of the molecule to be trigonal bipyramidal, seesaw, T-shaped, linear, octahedral, square pyramidal, or square planar. Seven examples and three interactive questions are provided in this animated activity.

In this brief object, learners examine the direct relationship between the volume of a gas sample and the number of moles of gas. A problem is presented so students can test their knowledge of Avogadro's Law.

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.

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

In this animated and interactive object, learners observe how two, three, or four groups of electrons around the central atom cause the shape of the molecule to be linear, trigonal planar, bent, tetrahedral, or pyramidal. Seven examples and eight interactive questions are provided.

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

In this learning activity learners will be hear about aspergillus found on marijuana and the potential health hazards that can affect a property room manager. Learners will hear about preventative measures.

In this animated object, learners examine neutral fats, phospholipids, and cholesterol. The molecular formula and general function for each are shown.

In this animated object, learners examine neutral fats, phospholipids, and cholesterol. The molecular formula and general function for each are shown.

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

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.

A crime scene photo for determination of time since death. The student will need to collect the evidence into the correct item.

This screencast shows how blood droplets are held together by a strong cohesive molecular force that produces surface tension in each drop and on the external force. Surface tension pulls the surface molecules of a liquid toward its interior, decreasing the surface area and causing the liquid to resist penetration.

Learners examine microscope images of blood agar and the various types of hemolysis that can be detected. A quiz completes the activity.