Across
- 3. Are also called energy levels
- 5. the revolving path traced by electrons
- 6. atomic number is six
- 7. modern periodic law
- 9. noble gases are also called as ----- gases
Down
- 1. elements from group 3 to 12 are-------- metals
- 2. proposed atomic theory
- 4. element which have no neutron
- 8. valence electons of noble gases