[General | States | Energies | Oxidation & Electrons]
[Appearance & Characteristics | Reactions | Other Forms]
[Radius | Conductivity
| Abundance | History]
| 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 | ||
| 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 | ||
| 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 | ||||
| Shells | 2,8,18,18,8,2 | Electron configuration | [Xe] 6s2 | ||
|---|---|---|---|---|---|
| Minimum oxidation number | 0 | Maximum oxidation number | 2 | ||
| Minimum common oxidation number | 0 | Maximum common oxidation number | 2 | ||
| Structure | bcc: body-centered cubic | Color | silvery-white | ||
|---|---|---|---|---|---|
| Uses | X-ray imaging agnt(BaSO4) | Toxicity | |||
| Hardness | mohs | Characteristics | soft | ||
| 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 | ||||
| Number of isotopes | 7 | Hydride(s) | BaH2 | ||
|---|---|---|---|---|---|
| Oxide(s) | BaO | Chloride(s) | BaCl2 | ||
| 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 | ||
| Thermal conductivity | 18.4 J/m-sec-deg | Electrical conductivity | 1/mohm-cm | ||
|---|---|---|---|---|---|
| Polarizability | 39.7 A^3 | ||||
| Source | Barite (sulfate) | Rel. abund. solar system | 0.652 log | ||
|---|---|---|---|---|---|
| Abundance earth's crust | 2.6 log | Cost, pure | 55 $/100g | ||
| Cost, bulk | $/100g | ||||