37Rb85.468
Rubidium
Alkali metal · element 37 · group 1, period 5
Quick facts
| Symbol | Rb |
|---|---|
| Atomic number | 37 |
| Relative atomic mass | 85.468 |
| Category | Alkali metal |
| Position | group 1, period 5 |
| State at 20 °C | Solid |
| Melting point | 39.3 °C |
| Boiling point | 688 °C |
| Density | 1.532 g/cm³ |
| Electronegativity | 0.82 |
| Electron configuration | [Kr] 5s1 |
About Rubidium
Rubidium has the symbol Rb and atomic number 37, which means every rubidium atom has 37 protons in its nucleus and, in a neutral atom, 37 electrons. At room temperature it is a solid.
Alkali metals are soft, shiny metals in group 1. They react quickly with water to make an alkaline solution and hydrogen gas, and they get more reactive going down the group.
It melts at 39.3 °C and boils at 688 °C.
Explore it
See where rubidium sits, and drag the temperature slider to watch it melt and boil, on the interactive periodic table. Practise with quizzes on OmniEx.