Across
- 4. Creator of the periodic table
- 6. Particles in the nucleus with no electrical charge.
- 7. Any of the possible energies an electron may have in an atom.
- 9. Average mass of the naturally occuring isotopes of an element.
- 10. Particles with a positive charge and are located in the nucleus.
- 11. Columns on the periodic table
Down
- 1. Tiny, very light particles with a negative electrical charge.
- 2. Number of protons in the nucleus of an atom.
- 3. Electrons in the outermost energy level of an atom.
- 5. Number of protons plus the number of neutrons.
- 8. Rows on the periodic table