Across
- 2. an atom that carries an electrical charge
- 3. formed compounds with oxygen called "oxides"
- 6. this group was found in nature combined with other elements
- 8. two atoms with different numbers of neutrons
- 10. number of protons
Down
- 1. an electron in the outermost energy level of an atom
- 4. tiny,very light particles and have a negative charge
- 5. equal to the number of protons plus neutrons
- 7. much larger and heavier than electrons and have a positive charge
- 9. large and heavy and has no electrical charge