Barium

Chemical, physical and material properties and data of the chemical element Barium.

Contents

General Information about Barium

Regular name Barium Chemical symbol Ba Other names Historical names Name meaning, origin Discovery (year) Occurence Position in the PSE Group membership

Atomar Properties of Barium

Atomic number Z 56 = number of protons Standard Atomic Weight 137.327 (7)

Electron configuration of Barium

1s	2s	2p	3s	3p	3d	4s	4p	4d	4f	5s	5p	5d	5f	6s	6p	6d	6f	7s	7p
2	2	6	2	6	10	2	6	10	2	6	2

Shorthand electron configuration of Barium: [Xe] 6s 2 .

Ionization Energies of Barium

The following table lists the ionization energies IE (ionization potentials); the IE is the energy required in electron volt (eV) per atom to separate a given electron from an Barium atom.

IE1	IE2	IE3	IE4	IE5	IE6	IE7	IE8
5.211664	10.00383	35.844	47.03	58	71	86	101

Isotopic Data of Barium

An overview of the nuclides as well as the isotopic data and properties are listed on the following page: Barium isotopes.

Chemistry of Barium

Oxidation states + 2 Electronegativity 0.9 (Pauling original)
0.89 (Pauling)
0.881 (Allen)
0.93 (Sanderson)
0.97 (Allred-Rochow)
2.4 eV (Pearson) Electron affinity 0.144 62(6) eV
13.954(6) kJ mol -1

Standard Electrode Potential

E 0 (V)	Symbol	N_ox	Name Ox. Name Red.	Ox. Red.	e -
-2.912	Ba	+ II 0	Barium cation Barium	Ba 2+ ⇄ Ba (s)	+ 2 e -

Material and Physical Properties

Melting point 727 °C Enthalpy of fusion (molar) 7.12 kJ mol -1 Boiling point 1845 °C Enthalpy of vaporization 150.9 kJ mol -1 Density 3.51 g cm -3