1. Chemistry Vocabulary 4 Feb. 6, 2012
isotope- variations of atoms of a particular chemical element, which have differing numbers of neutrons. (For example, carbon-12, carbon-13 and carbon-14 are three isotopes of the element carbon with mass numbers 12, 13 and 14 respectively )
Ion - is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge.

2. Chemistry Vocabulary 4 February 7, 2012
Mixture: The physical combination of two or more substances which CAN be separated by physical means. (ex. Trail Mix, Salt water)
Heterogeneous Mixture: A mixture that is unevenly mixed and the substances separate easily. (Ex Trail mix, granola bars)
Homogeneous Mixture: A substance that CAN NOT be separated into different substances easily. (Ex. salt water, smoke, milk, blood)

3. Chemistry Vocabulary 4 Feb. 8, 2012
Compound: Two or more elements that combine to form a new substance.
( Carbon + Oxygen yields CO2 gas)
Molecule: the simplest structural unit of a substance

4. Chemistry Vocabulary 4 February 9, 2012
Reactants: Chemicals which combine in a chemical reactions. The elements are being reacted in the experiment. (Na + Cl2)
Products: Chemicals which result from a chemical reaction. (Na + Cl NaCl)

5. Chemistry Vocabulary 4 February 10, 2012
Exothermic is a chemical reaction that releases energy in the form of light or heat.
Endothermic Reaction: describes a process or reaction in which the heat energy has been absorbed. (No visible sign of a reaction)