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