This short presentation provides a convenient introduction to the nitrogen group in the periodic table of elements. A graphic displays where they are placed in the periodic table. The nitrogen cycle is mentioned and ammonia is explained....

Properties and uses of the halogen elements are illuminated by this compact collection of slides. Examples of halogen reactions with alkali metals, hydrogen, and water are also explained. This is a nifty resource to support an...

Do you think Earth makes fun of other planets for having no life? The presentation covers the rotation and revolution of both the earth and our moon. It provides explanations for seasons, tides, and eclipses. Lesson is the 20th in a...

Force acts on objects in mysterious ways ... until now! A comprehensive presentation explains the balance of forces acting on objects. Learners draw free body diagrams to show these invisible forces and make force calculations.