Across
- 1. Energy levels where electrons are found.
- 5. Negatively charged particle.
- 6. Neutral particle in the nucleus.
- 8. The tendency of a substance to undergo chemical reactions.
Down
- 2. A pure substance consisting of only one type of atom.
- 3. Rows on the periodic table.
- 4. Positively charged particle in the nucleus.
- 7. Columns on the periodic table.