Sponsored by catalyst. A substance that increases the rate of a chemical reaction without actually undergoing any change itself. A negatively charged particle that is a constituent of an atom.
Electrons can move from atom to atom.
A molecule that is unstable and highly reactive because it contains at least one unpaired electron . Free radicals combine with molecules to generate further unpaired electrons, thereby starting off chain reactions. Free radicals can damage cell membranes and DNA, eventually causing cancer and other diseases. Extremely small tubes made from pure carbon. An old star with a very large radius and a relatively low surface temperature.