Across
- 3. positive mass at the center of the atom
- 5. Lightest element on the periodic table
- 6. the possible energies that electrons in an atom can have
- 7. negative subatomic particle
- 9. the number of protons in an atom
- 11. Element Fe on the periodic table
- 12. Element K on the periodic table
- 13. neutral subatomic particle
- 14. the first scientist to contribute to atomic theory
- 15. atoms of the same element with a different number of neutrons
- 16. scientist who discovered neutrons
Down
- 1. the number of protons and neutrons in the nucleus of an atom
- 2. this model is sometimes called the planetary model and places electrons on various energy levels outside the nucleus
- 4. Element 17 on the periodic table
- 7. visual model for the most likely location of electrons in an atom
- 8. positive subatomic particle
- 10. scientist who discovered the existence of electrons