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