Chemical Changes

Compound:A chemical combination of 2 or more elements.


Chemical bond:A link that atoms or electrically charged particles can form with each other.


Chemical formula:A way of using letters and numbers to show how much of each element is in a substances.

Ion:An elecrtically charged particle with unequal numbers of protons and electrons.

Molecule:A group of bonded atoms that acts like a single particle.

Chemical property:A way of describing how a substances change chemically with other substances.


Exothermic:A reaction that gives off heat.


Endothermic:A reaction that absorbs heat.