Across
- 4. A substance that cannot be decomposed into simpler substances by chemical means, an atom that is defined by its atomic number
- 5. the metals of Group 1 on the periodic table
- 7. the process of an unstable atomic nucleus losing energy by emitting radiation
- 9. an orbital around the atom's nucleus that has a fixed number electrons (usually two or eight)
- 12. the metals of Group 2 on the periodic table
- 13. combining two small nucleus, creates energy
- 14. mixture of evenly dispersed substances
- 15. fuel made from decaying plants and animals
- 17. Anything that has mass and occupies space.
- 18. a chemical reaction between an oxidant and fuel with heat and often light
- 19. A change in which one or more new substances are formed.
- 20. atoms containing the same number of protons but different numbers of neutrons
- 21. columns on the period table, 1-18
Down
- 1. An atom or a group of atoms that carries an electric charge
- 2. a subatomic particle with a net charge that is negative
- 3. two or more substances combined
- 6. occurs in nature used for enjoyment, or is economically important
- 7. Mass per unit Volume, how tightly packed the particles are
- 8. a chemical element in its smallest form
- 10. ongoing series of fission reactions
- 11. Oxidation of metals in the presence of air and moisture.
- 15. split of a large nucleus, creates energy and radiation
- 16. a substance that is made up of two or more chemically bonded elements