Across
- 4. any of the possible energies an electron may have in an atom.
- 7. have a positive charge
- 8. equal to the number of protons plus neutrons.
- 9. Have a negative electrical charge
- 10. Two atoms with different numbers of neutrons are called
Down
- 1. have no electrical charge
- 2. An atom that carries an electrical charge is called an
- 3. an electron in the outermost energy level of an atom.
- 5. number of protons
- 6. average mass of the naturally occurring isotopes of an element