Chemicool

Ba

56

137.33
Barium
General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles

General
Name Barium Symbol Ba
atomic number 56 Atomic weight 137.33
Density @ 293 K 3.51 g/cm3 Atomic volume 39.24 cm3/mol
Group Alkali Earth discovered 1808

States
state (s, l, g) s
melting point 998.2 K boiling point 2123 K
Heat of fusion 7.750 kJ/mol Heat of vaporization 142.0 kJ/mol
Back to the top

Energies
1st ionization energy 502.9 kJ/mole electronegativity 0.89
2nd ionization energy 965.2 kJ/mole electron affinity kJ/mole
3rd ionization energy kJ/mole Specific heat 0.204 J/gK
heat atomization 180 kJ/mole atoms

Oxidation & Electrons
Shells 2,8,18,18,8,2 electron configuration [Xe] 6s2
minimum oxidation number 0 maximum oxidation number 2
min. common oxidation no. 0 max. common oxidation no. 2
Back to the top

Appearance & Characteristics
structure bcc: body-centered cubic color silvery-white
uses X-ray imaging agnt(BaSO4) toxicity
hardness mohs characteristics soft

Reactions
reaction with air vigorous,wt/ht= BaO,Ba2N3 reaction with 6M HCl vigorous, = H2, BaCl2
reaction with 6M HCl vigorous, = H2, BaCl2 reaction with 15M HNO3 mild, = Ba(NO3)2
reaction with 6M NaOH passivated
Back to the top

Other Forms
number of isotopes 7 hydride(s) BaH2
oxide(s) BaO chloride(s) BaCl2

Radius
ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 222 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) 149 pm ionic radius (3+ ion) pm
Back to the top

Conductivity
thermal conductivity 18.4 J/m-sec-deg electrical conductivity 1/mohm-cm
polarizability 39.7 A^3

Abundance
source Barite (sulfate) rel. abund. solar system 0.652 log
abundance earth's crust 2.6 log cost, pure 55 $/100g
cost, bulk $/100g
Back to the top
World Wide Web presentation of Chemicool Periodic Table is © Copyright 1996-99 by David D. Hsu. Some data were provided by and used with the permission of JCE Software and is owned and copyright by the Division of Chemical Education, Inc. Additional data were provided by Perkin-Elmer through Peter Lykos of IIT. The information may not be redistributed without the permission of David Hsu or JCE Software.