Periodic table
Across
- 3. has only one energy level
- 6. Electrons per shell: 2, 8, 14, 2
- 7. silvery-white metal
- 9. atomic mass of 75
- 10. attic number 18
Down
- 1. atomic number 107
- 2. atomic weight of 127
- 4. very hard, and very resistant to heat
- 5. has 14 neutrons
- 8. Electron Configurations 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6