Tabla

Electronic ConfigurationXe 6s1

Melting Point28.6°C

Boiling Point678.6°C

Density1.873g cm⁻³

Description

Soft silvery-white metallic element belonging to group 1 of the periodic table. One of the three metals which are liquid at room temperature. ¹³³Cs is the natural, and only stable, isotope. Fifteen other radioisotopes exist. Caesium reacts explosively with cold water, and ice at temperatures above 157K. Caesium hydroxide is the strongest base known. Caesium is the most electropositive, most alkaline and has the least ionization potential of all the elements. Known uses include the basis of atomic clocks, catalyst for the hydrogenation of some organic compounds, and in photoelectric cells. Caesium was discovered by Gustav Kirchoff and Robert Bunsen in Germany in 1860 spectroscopically. Its identification was based upon the bright blue lines in its spectrum. The name comes from the latin word caesius, which means sky blue. Caesium should be considered highly toxic. Some of the radioisotopes are even more toxic.

Covalent Radius232pm

Double209pm

Ionisation Energies

Oxidation States0, +1

Uses

Used as a 'getter' to remove air traces in vacuum and cathode-ray tubes. Also used in producing photoelectric devices and atomic clocks. Since it ionizes readily, it is used as an ion rocket motor propellant.

Electron Affinity45.505kJ mol⁻¹

Electronegativity0.79PAULING

Atomic Volume70cm³ mol⁻¹

Atomic Radius267pm

Metallic Radius235pm

Van Der Waals Radius343pm

Sources

Found in pollucite [(Cs₄Al₄Si₉O₂₆).H₂O] and as trace in lepidolite.

Discovery

Discovered in 1860 by Gustov Kirchoff, Robert Bunsen in Germany

Name Origin

Latin: coesius (sky blue); for the blue lines of its spectrum.

CAS7440-46-2

Crust Abundance3mg kg⁻¹

Sea Abundance0.0003mg dm⁻³

Enthalpy of Vapourisation 68.3kJ mol⁻¹

Enthalpy of Fusion2.09kJ mol⁻¹

Enthalpy of Formation76.5kJ mol⁻¹

Specific Heat - 20°C0.241J (g ⋅ K)⁻¹

Thermal Conductivity35.9W (m ⋅ K)⁻¹

Isotope	Abundance	Half Life
133Cs	100%	-
134Cs	-	-
135Cs	-	-
137Cs	-	-

https://reuben.science

https://github.com/reubn/tabla

Using data from mendeleev.

MIT License Copyright (c) 2020 reubn Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. pb2bb3a9eb2b62a1fdf94