Across
- 4. horizontal row of elements in periodic table
- 6. made up by the protons and neutrons in nucleus
- 8. electrons in outermost energy level
- 9. vertical columns on periodic table
Down
- 1. ability of atom or atoms to bond or join with another atom
- 2. number of protons located in the nucleus
- 3. subatomic particle, no charge, inside nucleus of atom
- 4. subatomic particle, positive charge, inside nucleus of atom
- 5. subatomic particle, negative charge, outside nucleus of atom
- 7. one or two letters that represent elements on periodic table