Sodium Carbonate Cas 497-19-8 Wholesale

Sodium carbonate has the chemical formula Na₂CO₃, and its common names include soda ash, washing soda, and soda. Under normal circumstances, it is a white powder and a strong electrolyte. It has a density of 2.532 g/cm³ and a melting point of 851°C. It is easily soluble in water, soluble in anhydrous ethanol to a small extent, and insoluble in propanol. When dissolved in water, it undergoes a hydrolysis reaction, making the solution alkaline, and it has a certain degree of corrosiveness. It can react with acids in a neutralization reaction to form corresponding salts and release carbon dioxide. At high temperatures, it can decompose to form sodium oxide and carbon dioxide. When exposed to air for a long time, sodium carbonate can absorb moisture and carbon dioxide from the air, forming sodium bicarbonate and caking. It has strong hygroscopicity and tends to form hard lumps easily, but it does not decompose even at high temperatures. Sodium carbonate forms three hydrates with water: Na₂CO₃·10H₂O, Na₂CO₃·7H₂O, and Na₂CO₃·H₂O. Among them, Na₂CO₃·10H₂O is the most stable, and its heat of solution when dissolved in water is very small. It is widely used in the photography industry, where its commercial name is "carbon oxygen". Na₂CO₃·10H₂O, also known as crystal soda, is prone to efflorescence in dry air. In the past, crystal soda was often used for household washing and wool washing, hence it was also called "washing soda". In the past, people in China traditionally used "block alkali" which could both wash clothes and leaven dough. It was made by stirring soda ash with a large amount of water (with some baking soda (NaHCO₃) added), and its water content was over 50%. When sodium carbonate dissolves in water, it is an endothermic reaction, and it is prone to efflorescence in the air. Na₂CO₃·7H₂O is unstable and can only be precipitated from a saturated sodium carbonate solution within the temperature range of 32.5–36°C. Sodium carbonate is a salt of a weak acid and a strong base (soda ash is a salt, not a base, but its solution is strongly alkaline). Sodium carbonate produced by chemical methods is purer than natural alkali, so people call it "soda ash".