37Rb85.468
Rubidium
Alkali Metal
Solid at STP
Period 5Group 1Block SDiscovered 1861
[Kr]5s1
Rubidium is a chemical element with symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group, with an atomic mass of 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other alkali metals, such as very rapid oxidation in air.
📖 Read more on Wikipedia →Atomic Properties
| Atomic Number | 37 |
| Atomic Mass | 85.468 u |
| Electron Configuration | [Kr]5s1 |
| Oxidation States | +1 |
| Electronegativity | 0.82 (Pauling) |
| Atomic Radius | 303 pm |
| Ionization Energy | 4.177 eV |
| Electron Affinity | 0.468 eV |
| Block | S |
Physical Properties
| Appearance | grey white |
| Standard State | Solid |
| Melting Point | 312.46 K (39.3 °C) |
| Boiling Point | 961 K (687.9 °C) |
| Density | 1.53 g/cm³ |
| Molar Heat | 31.06 J/(mol·K) |
| CPK Color | #702EB0 |
Classification
| Category | Alkali Metal |
| Group Block | Alkali metal |
| Period | 5 |
| Group | 1 |
| Block | S |
Discovery
| Year Discovered | 1861 |
| Discovered By | Robert Bunsen |
| Electron Shells | 2, 8, 18, 8, 1 |