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 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance


Name: Cesium Symbol: Cs
Group: Alkali Met. Atomic weight: 132.9054
Density @ 293 K: 1.873 g/cm3 Atomic volume: 71.07 cm3/mol
Group: Alkali Met. discovered: 1860


state (s, l, g): s
melting point: 301.6 K boiling point: 978 K
Heat of fusion: 2.092 kJ/mol Heat of vaporization: 67.740 kJ/mol


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


reaction with air: vigorous, =>CsO2
reaction with 6M HCl: vigorous, =>H2, CsCl 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(s): CsH
oxide(s): Cs2O chloride(s): CsCl


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


thermal conductivity: 35.9 J/m-sec-deg
electrical conductivity: 48.9 1/mohm-cm polarizability: 59.6 A^3


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