Name: Thallium
Symbol: Tl
Atomic Number: 81
Atomic Mass: 204.3833 amu
Melting Point: 303.5 °C (576.65 °K, 578.3 °F)
Boiling Point: 1457.0 °C (1730.15 °K, 2654.6 °F)
Number of Protons/Electrons: 81
Number of Neutrons: 123
Crystal Structure: Hexagonal
Density @ 293 K: 11.85 g/cm3
Color: bluish
Atomic Structure
![[Bohr Model of Thallium]](b0081.gif) |
Number of Energy Levels: 6 First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 32 Fifth Energy Level: 18 Sixth Energy Level: 3 |
Isotopes
| Isotope | Half Life |
| Tl-200 | 1.08 days |
| Tl-201 | 3.03 days |
| Tl-202 | 12.23 days |
| Tl-203 | Stable |
| Tl-204 | 3.78 years |
| Tl-205 | Stable |
| Tl-206 | 4.2 minutes |
| Tl-207 | 4.77 minutes |
| Tl-208 | 3.05 minutes |
| Tl-209 | 2.2 minutes |
| Tl-210 | 1.3 minutes |
Facts
Date of Discovery: 1861Discoverer: Sir William Crookes
Name Origin: From the Greek word thallos (young shoot)
Uses: rat and ant poisons, detecting infrared radiation
Obtained From: crookesite, hutchinsonite, lorandite
Information provided by: http://www.chemicalelements.com