Across
- 4. Early model describing atoms as indivisible particles
- 7. Atoms of the same element with different numbers of neutrons
- 9. Chart organizing elements by atomic number and properties
- 10. Neutral subatomic particle in the nucleus
- 12. Standard unit for measuring atomic mass
- 13. Number of protons in an atom
Down
- 1. Weighted average of all isotopes of an element
- 2. Positively charged particles in the nucleus
- 3. Vertical column on the periodic table
- 5. Center of an atom containing protons and neutrons
- 6. Negatively charged subatomic particle
- 8. NUMBER Sum of protons and neutrons in an atom
- 9. Horizontal row on the periodic table
- 11. Stream of electrons used in early atomic experiments
- 12. Smallest unit of an element