Khan Academy
Khan Academy: Single and Multiple Covalent Bonds
Explains what covalent bonds are and the difference between them and ionic bonds. Discusses the properties of polar and non-polar covalent bonds, and single and multiple covalent bonds, and gives analogies and examples of how covalent...
Khan Academy
Khan Academy: Molecules and Compounds
Article defines and explains compounds which are either ionic or covalent and molecules which are the simplest unit of a covalent compound. Molecules can be represented in many different ways.
Khan Academy
Khan Academy: Biology: Chemistry of Life: Chemical Bonds
Review over covalent, hydrogen, and ionic bonding in this article. Learn how molecules are held together by chemical bonds.