Barium (Ba)
Barium
Barium (Ba) is an alkaline earth metal in period 6, group 2. Its relative atomic mass is 137.33 and the molar mass of the atom is 137.33 g/mol.
Atomic number 56
Atomic mass 137.33
Molar mass 137.33 g/mol
Category Alkaline earth metal Solid
Properties of barium
| Atomic number | 56 |
|---|---|
| Symbol | Ba |
| Latin name | Barium |
| Relative atomic mass | 137.33 |
| Molar mass | 137.33 g/mol |
| Group, period, block | 2, 6, s |
| Category | Alkaline earth metal |
| State at 20 °C | Solid |
| Electron configuration | [Xe] 6s² |
| Electronegativity (Pauling) | 0.89 |
| Atomic radius | 215 pm |
Electron configuration of barium
Electrons per shell
K2L8M18N18O8P2
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 6s²
Noble-gas notation
56 protons · 56 electrons[Xe] 6s²
Formula and compounds of barium
Simple substanceBabariumMolar mass of Ba: 137.33 g/mol
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Frequently asked questions
The relative atomic mass of barium is 137.33, so the molar mass of the atom is 137.33 g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 6s². Noble-gas notation: [Xe] 6s².