The term activation energy refers to the minimum amount of energy required for a chemical reaction to occur. Most reactions require that atoms and molecules crash into each other with a great deal of force. These violent collisions must occur with...

In chemistry, activation energy, also called threshold energy, is a term introduced in 1889 by Svante Arrhenius that is defined as the energy that must be overcome in order for a chemical reaction to occur. Activation energy may otherwise be denoted as...

Environmentalism: The same day that Al Gore lectured Congress about man-made global warming, NASA made a startling announcement: The sun is hotter and more active than thought.NASA detailed new observations of solar explosions from a powerful space telescope that recently beamed back X-ray images of...