55
Cs
132.9054
Cesium
General | States | Energies | Oxidation & Electrons |
Appearance & Characteristics | Reactions |
Other Forms Radius | Conductivity | Abundance



General:

Name: Cesium Symbol: Cs
Group: Alkali Met. Atomic weight: 132.9055
Density @ 293 K: 1.873 g/cm3 Atomic volume: 71.07 cm3/mol
Group: Alkali Met. Discovered: 1860

States

State (s, l, g): solid
Melting point: 301.6 K   (28.4 oC) Boiling point: 943 K   (670 oC)
Heat of fusion: 2.092 kJ/mol Heat of vaporization: 67.740 kJ/mol

Energies

1st ionization energy: 375.7 kJ/mole
Electronegativity: 0.79 2nd ionization energy: 2421.8 kJ/mole
Electron affinity: 45.506 kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.24 J/gK Heat atomization: 79 kJ/mole atoms

Oxidation & Electrons

Shells: 2,8,18,18,8,1 Electron configuration: [Xe] 6s1
Minimum oxidation number: 0 Maximum oxidation number: 1
Min. common oxidation no.: 0 Max. common oxidation no.: 1

Appearance & Characteristics

Structure: bcc: body-centered cubic Color: yellow/silvery
Uses: photocells, IR lamps Toxicity:
Hardness: 0.2 mohs Characteristics: softest metal, melts near room temp.

Reactions

Reaction with air: vigorous, => CsO2
Reaction with 6 M HCl: vigorous, => H2, CsCl Reaction with 6 M HCl: vigorous, => H2, CsCl
Reaction with 15 M HNO3: vigorous, => CsNO3 Reaction with 6 M NaOH: vigorous, => H2, CsOH

Other Forms

Number of isotopes: 1 Hydride(s): CsH
Oxide(s): Cs2O Chloride(s): CsCl

Radius

Ionic radius (2- ion): pm Ionic radius (1- ion): pm
Atomic radius: 265 pm Ionic radius (1+ ion): 181 pm
Ionic radius (2+ ion): pm Ionic radius (3+ ion): pm

Conductivity

Thermal conductivity: 35.9 J/m-sec-deg
Electrical conductivity: 48.9 1/mohm-cm Polarizability: 59.6 A^3

Abundance

Source: Li extractn by-product
Rel. abund. solar system: -0.429 log Abundance earth's crust: 0 log
cost, pure: 1100 $/100g cost, bulk: $/100g