Atomic number:11

Group numbers:1

Period:3

Electronic configuration:[Ne] 3s¹

Formal oxidation number:+1

Electronegativities:0.93

Atomic radius / pm:185.8

Relative atomic mass:22.98976928 ± 0.00000002

 

Sodium was discovered by Sir Humphry Davy (GB) in 1807. The origin of the name comes from the Latin word natrium meaning sodium carbonate. It is a soft silvery-white metal. Fresh surfaces oxidize rapidly. It reacts vigorously, even violently with water giving off flammable gas. Sodium burns in air with a brilliant white flame. Sodium is obtained by electrolysis of melted sodium chloride (salt), borax and cryolite. Metallic sodium is vital in the manufacture of organic compounds. Sodium chloride (NaCl) is table salt. Liquid sodium is used to cool nuclear reactors.

Density / g dm^-3:971 (293 K)

 928 (m.p.)

Molar volume / cm³mol^-1:23.68 (293 K)

 24.77 (m.p.)

Electrical resistivity / μΩcm:4.2 (20 °C)

Thermal conductivity / W m^-1K^-1:141

Melting point / °C:97.72

Boiling point / °C:883

Heat of fusion / kJ mol^-1:2.64

Heat of vaporization / kJ mol^-1:99.2

Heat of atomization / kJ mol^-1:107.566

1st ionization energy / kJ mol^-1:495.85

2nd ionization energy / kJ mol^-1:4562.48

3rd ionization energy / kJ mol^-1:6910.33

in the atmosphere / ppm:-

in the Earth's crust / ppm:23000

in the oceans / ppm:10600