In this screencast, learners examine the properties of the hydrogen bond and how the bond changes when hair is shampooed or styled.

In this interactive object, students examine a type of chemical bond known as the "hydrogen bond."

In this animated lesson, learners read about the disulfide bond, the second strongest chemical bond in the hair. This bond can only be altered by chemicals.

In this animated object, learners examine how changes in pH affect the salt bonds in strands of hair.

In this screencast, learners examine the properties of the peptide bond and how the bond relates to the structure of hair.

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.

In this animated object, learners examine the formation of ester bonds in the synthesis of lipids using triglyceride biosynthesis as an example. Ester bond formation is described as a dehydration synthesis reaction.

In this animated object, learners examine the formation of peptide bonds through dehydration synthesis.

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

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

In this animated object, learners view hydrogen and hydroxide ions in a solution. A brief quiz on the basic principles of the term pH completes the activity.

The definition of an isotope is illustrated using the three isotopes of carbon. The three isotopes of hydrogen are discussed as exceptions.

In this interactive and animated object, students distribute the valence electrons in simple covalent molecules with one central atom. Six rules are followed to show the bonding and nonbonding electrons in Lewis dot structures. The process is well illustrated with eight worked examples and two interactive practice problems.

Ions are electrically charged particles obtained from an atom or from a chemically bonded group of atoms by adding or removing electrons. Eight examples illustrate the number of protons, neutrons, and electrons in positive ions (cations) and in negative ions (anions).

Students read about the process of hair growth beginning with the joining together of amino acids.