Sodium belongs to the family of elements called alkali metals. The atomic number of sodium is 11 and its atomic weight is 22.98976928 atomic mass units or grams per mole. The symbol for sodium is Na.
The electronic configuration of sodium is [Ne] 3S1 and it has one valence electron in the outermost shell. Sodium is silver-white and a highly reactive metal. It is placed in Period 3 and Group 1 or the S-block of elements in the Periodic Table of Elements. It exists as a solid at room temperature, but must be stored in kerosene due to its reactive nature. It melts at 97.80 degrees Celsius and has a density of 0.97 grams per cubic centimeter.