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

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.

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

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

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.

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

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.

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.

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

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.

In this learning object, you will learn about four blood osmolality and volume regulators, their sites of production, their sites of action, and the results of those actions.

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

Learners examine graphs and read that the heat of fusion is the heat energy absorbed by one mole of solid as it is converted to liquid, while the heat of vaporization is the heat energy absorbed by one mole of liquid as it is converted to gas.

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

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.