Across
- 3. atom with neutral charge
- 6. number of protons in atom
- 9. an electron in the outermost energy level of an atom
- 10. average mass of the naturally occurring isotopes of an element
Down
- 1. An atom that carries an electrical charge
- 2. equal to the number of protons plus neutrons
- 4. Two atoms with different numbers of neutrons
- 5. atom with positive charge
- 7. any of the possible energies an electron may have in an atom
- 8. atom with negative electrical charge