 |
| General |
| Name | Caesium |
| Symbol | Cs |
| Number | 55 |
| Group Number | 1 |
| Group | Alkali metals |
| Block | s |
| Density | 1.873 g/cm3 |
| Atomic Weight | 132.9054 g/mol |
| Atomic Volume | 71.07 cm3/mol |
| Discover | 1860 |
|
| States |
| State | Solid |
| Melting Point | 301.59 K |
| Boiling Point | 944 K |
| Triple Point | Nil |
| Critical Point | 1938 K |
| Heat of Fusion | 2.09 kJ/mol |
| Heat of Vaporization | 63.9 kJ/mol |
|
| Energies |
| First Ionization Energy | 375.7 kJ/mole |
| Second Ionization Energy | 2421.8 kJ/mole |
| Third Ionization Energy | Nil |
| Electronegativity | 0.79 |
| Electron Affinity | 45.506 kJ/mole |
| Specific Heat | 0.24 J/gK |
| Heat Atomization | 79 kJ/mole atoms |
|
| Oxidation and Electrons |
| Shells | 2,8,18,18,8,1 |
| Electron Configuration | [Xe] 6s1 |
| Minimum Oxidation Number | 0 |
| Maximum Oxidation Number | 1 |
| Minimum Common Oxidation Number | 0 |
| Maximum Common Oxidation Number | 1 |
|
| Appearance and Characteristics |
| Crystal Structure | body centered cubic |
| Characteristics | softest metal |
| Color | yellow/silvery |
| Uses | photocells, IR lamps |
| Hardness | 0.2 mohs |
| Toxicity | None |
|
| Reactions |
| Reaction with Air | vigorous, =>CsO2 |
| Reaction with 6M HCl | vigorous, =>H2, CsCl |
| Reaction with 15M HNO3 | vigorous, =>CsNO3 |
| Reaction with 6M NaOH | vigorous, =>H2, CsOH |
|
| Other Forms |
| Number of Isotopes | 1 |
| Hydride | CsH |
| Oxide | Cs2O |
| Chloride | CsCl |
|
| Radius |
| Atomic Radius | 265 pm |
| Ionic Radius (1+ ion) | 181 pm |
| Ionic Radius (1- ion) | Nil |
| Ionic Radius (2+ ion) | Nil |
| Ionic Radius (2- ion) | Nil |
| Ionic Radius (3+ ion) | Nil |
|
| Conductivity |
| Thermal Conductivity | 35.9 J/m-sec-deg |
| Electrical Conductivity | 48.9 1/mohm-cm |
| Polarizability | 59.6 A3 |
|
| Abundance |
| Source | Li extractn by-product |
| Relation Abundance Solar System | -0.429 log |
| Abundance Earth's Crust | Nil |
|
