Across
- 2. Symbol for water
- 6. Center of an atom
- 10. Subatomic particle with no charge
- 11. Horizontal row in periodic table
- 16. The pH of a neutral substance
- 17. Negatively charged particle
- 19. Smallest particle of an element
- 20. Number of protons in an atom
- 21. Gas needed for combustion
Down
- 1. Mixture that looks uniform
- 3. Device used to measure mass
- 4. Tool used to heat substances
- 5. Table organizing elements
- 7. Vertical column in the periodic table
- 8. Process that forms new substances
- 9. Bond formed by sharing electrons
- 12. Abbreviation for sodium chloride
- 13. Simplest type of pure substance
- 14. Positively charged particle
- 15. Unit of temerature in science
- 18. Electron shell or ______ level
- 20. Opposite of base