Rb
Rubidium
Rubidium is a chemical element with the symbol Rb and atomic number 37. It has a standard atomic weight of 85.468, sits in period 5 and group 1, and is classified as an alkali metal.
Properties
| Symbol | Rb |
|---|---|
| Atomic number | 37 |
| Standard atomic weight | 85.468 |
| Category | Alkali metal |
| Group | 1 |
| Period | 5 |
| Electron configuration | [Kr] 5s1 |
| Outer-shell electrons | 1 |
The figure of 85.468 is a standard atomic weight.
Compounds containing rubidium
1 of the compounds in this reference contain Rb, listed by the fraction of their mass it makes up.
| Compound | Formula | Atoms | % by mass |
|---|---|---|---|
| rubidium chloride | ClRb | 1 | 70.7% |
Calculate with rubidium
- Molar mass of any formula containing it
- Electron configuration, including ions
- Effective nuclear charge by Slater's rules
- Average atomic mass from isotope abundances
Group 1
Atomic weights are the IUPAC 2021 standard values, abridged to the conventional five significant figures. Group, period, category and electron configuration are derived from the atomic number rather than stored, so they cannot drift out of step with it.