|Class 11 Chemistry The S Block Elements||Sodium chloride|
Sodium chloride is derived by mining the deposits and crystallization of brine solution. Brine solution is produced as a result of the dissolution of deposits in water. It contains sodium sulphate, calcium sulphate. Calcium chloride and magnesium chloride being deliquescent exist as impurities in brine solution. Evaporation of brine solution is followed by formation of crystals containing the impurities. Filtration of this solution by adding small amount of water followed by saturation of solution with hydrogen chloride gas gives pure sodium chloride.