About This Lesson
Watch how two hydrogen atoms collide and stick together to make a hydrogen molecule, H2. See how hydrogen atoms collide and chemically bond with oxygen to form water, H2O, with nitrogen to form ammonia, NH3, and with carbon to form methane, CH4. The chemical formula of these substances are explained, and the connection between the microscopic molecules that make up a substance and its macroscopic properties is shown. Also, the difference between an element and a compound is explained.