19K39.098
Potassium
Alkali metal · element 19 · group 1, period 4
Quick facts
| Symbol | K |
|---|---|
| Atomic number | 19 |
| Relative atomic mass | 39.098 |
| Category | Alkali metal |
| Position | group 1, period 4 |
| State at 20 °C | Solid |
| Melting point | 63.5 °C |
| Boiling point | 759 °C |
| Density | 0.89 g/cm³ |
| Electronegativity | 0.82 |
| Electron configuration | [Ar] 4s1 |
About Potassium
Potassium has the symbol K and atomic number 19, which means every potassium atom has 19 protons in its nucleus and, in a neutral atom, 19 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 63.5 °C and boils at 759 °C.
Explore it
See where potassium sits, and drag the temperature slider to watch it melt and boil, on the interactive periodic table. Practise with quizzes on OmniEx.