Across
- 3. A horizontal row in the periodic table.
- 5. The smallest unit of matter.
- 8. The center of an atom.
- 9. A particle that orbits the nucleus.
- 10. A particle in the nucleus with a positive charge.
Down
- 1. An element that usually loses electrons.
- 2. An element that usually gains or shares electrons.
- 4. A vertical column in the periodic table.
- 6. A particle in the nucleus with no charge.
- 7. How many electrons an atom can gain, lose, or share.