11Na22.990
Alkali Metals-block
Sodium
Element 11 on the periodic table, symbol Na, group 1, period 3.
Sodium /ˈsoʊdiəm/ is a chemical element with symbol Na (from Ancient Greek Νάτριο) and atomic number 11. It is a soft, silver-white, highly reactive metal. In the Periodic table it is in column 1 (alkali metals), and shares with the other six elements in that column that it has a single electron in its outer shell, which it readily donates, creating a positively charged atom - a cation.
Appearance: silvery white metallic
Properties
- Atomic Number
- 11
- Atomic Mass
- 22.9898 u
- Group
- 1
- Period
- 3
- Block
- s-block
- Category
- Alkali Metal
- State at 25 °C
- Solid
- Melting Point
- 370.9 K · 97.8 °C
- Boiling Point
- 1,156.1 K · 882.9 °C
- Density
- 0.968 g/cm³
- Atomic Radius
- 180 pm
- Electronegativity
- 0.93
- Oxidation States
- +1
- Abundance in Crust
- 2.36e+4 mg/kg
- Discovered
- 1807
- Discovered By
- Humphry Davy
Electron Configuration
[Ne] 3s1
1s2 2s2 2p6 3s1
Ionisation Energies (kJ/mol)
- 1. 495.8
- 2. 4,562
- 3. 6,910.3
- 4. 9,543
- 5. 13,354
- 6. 16,613
- 7. 20,117
- 8. 25,496
Elements near Sodium
Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.