Question

Recrystallisatiin of sodium carbonate gives what

Answer 1

The present invention provides a process for producing sodium carbonate monohydrate crystals by introduction of anhydrous sodium carbonate into a saturated sodium carbonate brine solution under conditions in which sodium carbonate monohydrate formation is favored. As the anhydrous sodium carbonate dissolves, the brine becomes supersaturated resulting in relief of supersaturation by formation of sodium carbonate monohydrate crystals. The process includes controlling supersaturation and its relief to achieve growth of existing sodium carbonate monohydrate crystals rather than nucleation and formation of new sodium carbonate monohydrate crystals. The resulting crystals are separated from insoluble impurities on a size separation basis.

Answer 2

Sodium carbonate, Na2CO3, (also known as washing soda, soda ash and sodacrystals, and in the monohydrate form as crystal carbonate) is the water-solublesodium salt of carbonic acid. It most commonly occurs as a crystalline decahydrate, which readily effloresces to form a white powder, the monohydrate.