Atomica
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10. Neon12. Magnesium
11Na22.99

Sodium

Alkali metals

Soft, very reactive metals with one outer electron. They react with water to make alkaline solutions.

[Ne] 3s¹

Atomic number
11
Atomic mass
22.99
Protons
11
Neutrons
12 (most common)
Electrons
11
Shells
2, 8, 1
State at 25 °C
Solid
Position
Group 1, period 3
Proton (+)Neutron (0)Electron (−)
Discovered byHumphry Davy, 1807Humphry Davy: 7 elements

Davy passed electricity through molten caustic soda and got shiny metal beads that burst into flame on water.

Did you know?

  • It is soft enough to cut with a butter knife.
  • It is stored under oil because it reacts violently with water.

Where it's found

  • Table salt (sodium chloride)
  • Seawater and rock salt

What it's used for

  • Table salt
  • Baking soda
  • Yellow street lamps

Try it

Grow salt crystalsSafe at home
  1. 1Stir salt into warm water until no more dissolves.
  2. 2Pour it into a shallow dish and leave it somewhere warm.
  3. 3Check every day for a week.

What you'll see: Small cube-shaped crystals appear as the water evaporates.