Chemistry

12345678910
Across
  1. 4. protons + neutrons
  2. 6. inventor of periodic table
  3. 8. consists of protons and neutrons
  4. 9. positively charged particle
  5. 10. neutrally charged particle
Down
  1. 1. one or two letters than represent an element
  2. 2. electron in the outer shell
  3. 3. basic unit of a chemical element
  4. 5. number of protons in nucleus
  5. 7. negatively charged particle