19K39.098
Potassium
Alkali metalsSoft, very reactive metals with one outer electron. They react with water to make alkaline solutions.
[Ar] 4s¹
- Atomic number
- 19
- Atomic mass
- 39.098
- Protons
- 19
- Neutrons
- 20 (most common)
- Electrons
- 19
- Shells
- 2, 8, 8, 1
- State at 25 °C
- Solid
- Position
- Group 1, period 4
Proton (+)Neutron (0)Electron (−)
Discovered byHumphry Davy, 1807Humphry Davy: 7 elements
Potassium was the first metal ever isolated using electricity. Davy made it from potash, which gave it its name.
Did you know?
- It reacts with water so fast that it bursts into a lilac flame.
- Your nerves need potassium to send signals.
Where it's found
- Bananas, potatoes and spinach
- Soil minerals
What it's used for
- Fertilisers (potash)
- Soaps
Try it
There's no safe home experiment for Potassium. Explore it with the animated atom above instead.