Across
- 1. electrons an electron in the outermost energy level of an atom
- 3. weight average mass of the naturally occurring isotopes of an element
- 6. particles that have no electrical charge
- 7. particles that have a positive charge
- 8. levels any of the possible energies an electron may have in an atom
Down
- 2. particles that are have a negative charge
- 4. two atoms with different numbers of neutrons
- 5. an atom that carries an electrical charge