Across
- 2. chemical ________ is the force that holds two atoms together
- 5. center of an atom contains protons and neutrons
- 7. the number of protons in the nucleus of an atom
- 9. a horizontal row of elements in the periodic table
- 10. an electron that is found in the outermost shell of an atom and that determines the atom's chemical properties
- 12. a bond formed by the attraction between positively charged metal ions and the "sea of electrons" around them
- 14. a positively charged subatomic particle
- 15. a vertical column of elements in the periodic table
Down
- 1. a bond formed when atoms share one or more pairs of electrons
- 3. a subatomic particle that has no charge and that is found in the nucleus of an atom
- 4. an atom with the same number of protons and a different number of neutrons
- 6. the sum of the number of neutrons and protons in an atomic nucleus
- 8. a negatively charged subatomic particle
- 11. the basic unit of a chemical element
- 13. chemical bond resulting from the attraction between oppositely charged ions