Search results
Results From The WOW.Com Content Network
Hard water usually contains calcium or magnesium ions. Sodium carbonate is used for removing these ions and replacing them with sodium ions. [16] Sodium carbonate is a water-soluble source of carbonate. The calcium and magnesium ions form insoluble solid precipitates upon treatment with carbonate ions:
The very pure and finely divided precipitate of calcium carbonate that is generated is a valuable by-product used in the manufacture of toothpaste. The salting-out process used in the manufacture of soaps benefits from the common-ion effect. Soaps are sodium salts of fatty acids. Addition of sodium chloride reduces the solubility of the soap salts.
Softened water (measured as residual sodium carbonate index) in which calcium and magnesium have been partly replaced by sodium is not suitable for irrigation use, as it tends to cause the development of alkali soils. [28] Non-chemical devices are often used in place of traditional water softening for this application.
The reduction of blowdown by dealkalization keeps the water treatment chemicals in the boiler longer, thus minimizing the amount of chemicals required for efficient, noncorrosive operation. [2] Carbonate and bicarbonate alkalinities are decomposed by heat in boiler water releasing carbon dioxide into the steam.
As water evaporates in the boiler, the concentration of sodium carbonate increases in the boiler. In high pressure boilers, sodium carbonate is used in softening of water by lime soda process, due to this some sodium carbonate maybe left behind in the water.
A spectator ion is an ion that exists both as a reactant and a product in a chemical equation of an aqueous solution. [1]For example, in the reaction of aqueous solutions of sodium carbonate and copper(II) sulfate:
Water-reactive substances [1] are those that spontaneously undergo a chemical reaction with water, often noted as generating flammable gas. [2] Some are highly reducing in nature. [ 3 ] Notable examples include alkali metals , lithium through caesium , and alkaline earth metals , magnesium through barium .
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.