Soda is a transliteration of SODA, and its chemical formula is Na2CO3. It has many names, the scientific name is sodium carbonate, the common name is soda, and it is also called soda ash or baking soda powder. There are three kinds of sodium carbonate hydrate with crystal water: sodium carbonate monohydrate (Na2CO3 7H2O), sodium carbonate heptahydrate (Na2CO3 7H2O) and sodium carbonate decahydrate (Na2CO310H2O). Sodium carbonate decahydrate is also called alkali washing, alkali washing or crystallization alkali.
Anhydrous sodium carbonate is white powder or fine particles, easily soluble in water, and its aqueous solution is alkaline. It has strong hygroscopicity and can absorb moisture in the air to form lumps. Sodium carbonate decahydrate is a colorless crystal. If left in the air at room temperature, it will lose its crystal water and become sodium carbonate monohydrate. When heated, both sodium carbonate decahydrate and sodium carbonate monohydrate will become anhydrous sodium carbonate. Sodium carbonate is very stable and is not easy to decompose when heated. Carbon dioxide can be released when it meets acid;
Na2CO3+2HCl====2NaCl+H2O+CO2↑？
Sodium carbonate solution can also absorb carbon dioxide to form sodium bicarbonate;
Sodium carbonate +H2O+ carbon dioxide = = = sodium bicarbonate
Among the three kinds of soft drinks, sodium carbonate is the most widely used. It is a very important chemical product and an important raw material for glass, soap, textile, paper making, leather making and other industries. It is also used in metallurgical industry and water purification. It can also be used to make other sodium compounds. As early as the eighteenth century, it was listed as one of the basic chemical raw materials-diacid dibasic with sulfuric acid, hydrochloric acid, nitric acid and caustic soda. In daily life, soda also has many uses. For example, it can be directly used as a detergent. Adding soda when steaming steamed bread can neutralize the acidic substances produced in the fermentation process.
2.baking soda
The chemical formula of baking soda is NaHCO3. It also has many names, the scientific name is sodium bicarbonate, also known as sodium bicarbonate or acid carbon.
Sodium. In addition to baking soda, there are baking soda, fermented soda and heavy alkali.
Baking soda is a white crystal, easily soluble in water, and its aqueous solution is weakly alkaline. In hot air, it can slowly decompose and release a part of carbon dioxide; When heated to 270℃, carbon dioxide is completely decomposed and released.
2 nahco3 = = = Na2CO3+H2O+CO2 writes that it can also react with acids (such as hydrochloric acid) to release carbon dioxide:
Sodium bicarbonate+hydrochloric acid = = = sodium chloride +H2O+ carbon dioxide
These characteristics of baking soda make it have many important uses in production and life. In fire extinguishers, it is one of the raw materials to produce carbon dioxide; In the food industry, it is the main raw material of baking powder; It is also a common raw material for making cold drinks; Medically, it is a medicine for treating hyperacidity.
3.baking soda
Baking soda is the common name of sodium thiosulfate, also called hypo (transliteration of hypo), and it has five crystal waters (Na2S2O3 5h2o), so it is also called sodium thiosulfate pentahydrate.
Sodium bicarbonate is colorless and transparent crystal, easily soluble in water, and its aqueous solution is weakly alkaline. Weathering in dry air above 33℃, losing crystal water. It is stable in neutral and alkaline solutions and will decompose rapidly in acidic solutions.
na 2 S2 o 3+2 HCl = = = = 2 NaCl+H2O+S↓+SO2↑？
Soda has a strong complexing ability and can form a complex with silver bromide. The reaction formula: agbr+2na2s2o3 = = nabr+na3 [ag (s2o3) 2]. According to this property, it can be used as a fixing agent. During phase washing, excessive baking soda reacts with the silver bromide of the unexposed part of the negative film and is converted into soluble Na2 [Ag (S2O3) 2], and AgBr is removed, thus fixing the developed part.
Soda also has strong reducibility, which can reduce substances such as chlorine.
Na2S2O3+4cl2+5h2o = = H2SO4+2nac+6HCl, so it can be used as dechlorination agent for bleached cotton fabrics. Similarly, iodine stains on fabrics can also be removed with it.
In addition, baking soda is also used for tanning, electroplating and extracting silver from ores.