Name: Cesium
Symbol: Cs
Atomic Number: 55
Atomic Mass: 132.90546 amu
Melting Point: 28.5 °C (301.65 °K, 83.3 °F)
Boiling Point: 678.4 °C (951.55005 °K, 1253.12 °F)
Number of Protons/Electrons: 55
Number of Neutrons: 78
Crystal Structure: Cubic
Density @ 293 K: 1.873 g/cm3
Color: silver
British Spelling: Caesium
IUPAC Spelling: Caesium
Atomic Structure
![[Bohr Model of Cesium]](b0055.gif) |
Number of Energy Levels: 6 First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 18 Fifth Energy Level: 8 Sixth Energy Level: 1 |
Isotopes
| Isotope | Half Life |
| Cs-126 | 1.6 minutes |
| Cs-129 | 1.3 days |
| Cs-131 | 9.7 days |
| Cs-132 | 6.4 days |
| Cs-133 | Stable |
| Cs-134 | 2.1 years |
| Cs-134m | 2.9 hours |
| Cs-135 | 2300000.0 years |
| Cs-136 | 13.2 days |
| Cs-137 | 30.2 years |
| Cs-138 | 32.2 minutes |
| Cs-139 | 9.3 minutes |
Facts
Date of Discovery: 1860Discoverer: Fustov Kirchoff
Name Origin: From the Latin word caesius (sky blue)
Uses: removes air traces in vacuum tubes
Obtained From: pollucite, lepidolite
Information provided by: http://www.chemicalelements.com