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Soda is acidic or alkaline
Soda is alkaline

Soda is a chemical raw material called anhydrous sodium carbonate, also known as soda ash, also known as lye, lye noodles, soda, sodium carbonate decahydrate, soda crystals, aqueous soda, washing soda, washing soda sodium, lye crystals, crystal soda.

Soda ash, scientific name sodium carbonate, also known as soda, alkali ash, an important basic chemical raw material, the main product of the soda ash industry. Usually white powder, easy to decompose at high temperature, soluble in water, aqueous solution is alkaline. Sodium carbonate and water into Na2CO3-10H2O, Na2CO3-7H2O, Na2CO3-H2O three kinds of hydrates, of which Na2CO3-H2O is the most stable, and dissolved in water dissolution heat is very small, more used in the photographic industry, the name of the commodity carbon dioxide. Na2CO3-10H2O, also known as the crystal alkali or washing alkali, dissolved in water is a heat-absorbing reaction, easy to weather in the air. Na2CO3-7H2O is unstable and can be precipitated from saturated solution of sodium carbonate only in the range of 32.5~36℃.

Soda ash

Chemical formula: Na2CO3

Molecular weight: 105.99

Common name: soda ash, soda rock, soda (Soda), mouth alkali (historically, it is usually transferred to the whole country through the Zhangjiakou and the Gubeikou, so it is also known as "mouth alkali".)

Appearance: white powder or fine-grained crystals (anhydrous pure)

Flavor: astringent

Soda Ash

Relative Density (water = 1): 2.532

Melting Point: 851 ℃

Classification: Strong alkali and weak acid salts **Note** (Soda Ash is not an alkali, it is a salt!) [1]

Chemical properties

1) The solution appears alkaline, can react with acid: Na2CO3 + 2HCl = 2NaCl + H2O + CO2↑

2) Na2CO3 reacts with alkali: Na2CO3 + Ca(OH)2 = CaCO3 ↓ + 2NaOH

3) Na2CO3, NaCl and salt Reaction: Na2CO3+BaCl2=BaCO3↓+2NaCl

4) Reaction of Na2CO3 with CO2: Na2CO3+CO2+H2O=2NaHCO3

Stability

Decomposes at high temperatures, producing sodium oxide and carbon dioxide. Prolonged exposure to air can absorb moisture and carbon dioxide in the air, generating sodium bicarbonate and forming hard lumps. Moisture absorption is very strong, it is easy to form hard lumps, and does not decompose at high temperatures. There are 3 kinds of sodium carbonate containing water of crystallization: Na2CO3-H2O, Na2CO3-7H2O and Na2CO3-10H2O.

Solubility

Easily soluble in water, slightly soluble in anhydrous ethanol, insoluble in propanol. Sodium carbonate is easily soluble in water, is a weak acid salt, dissolved in water after the hydrolysis reaction, so that the solution is alkaline, has a certain degree of corrosiveness, can be neutralized with the acid reaction to produce the corresponding salt and release carbon dioxide.

Use

Soda ash is mainly used in the production of glass, such as flat glass, bottle glass, optical glass and high-grade ware; in the chemical industry, it is used in the production of sodium salts, metal carbonates, bleach, fillers, detergents, catalysts and dyes, etc.; in metallurgy, it is used to remove sulfur and phosphorus, and is used in the beneficiation of minerals and the production of metals, such as copper, lead, nickel, tin, uranium, aluminum, etc.; in ceramics, it is used to make refractory materials and refractory materials. In the ceramic industry, it is used to produce refractory materials and glaze. In addition, industrial gas desulfurization, industrial water treatment, metal degreasing, cellulose and paper production, soap manufacturing, etc. also need soda ash.

Can be used directly as raw material for pharmaceutical industry. Can also be used in film production, tanning, mineral processing, smelting, metal heat treatment, as well as for fiber, rubber industry. At the same time used as wool detergent, foam fire extinguishing agent, as well as used in agriculture to soak seeds and so on. Fire-fighting equipment used in the production of acid and alkali fire extinguishers and foam fire extinguishers. Rubber industry with alum, H porous agent with the role of uniform porous for rubber, sponge production. Metallurgical industry as a flux for casting steel ingots. Mechanical industry is used as a molding aid for steel casting (sand). Printing and dyeing industry as dyeing and printing color fixing agent, acid and alkali buffer, fabric dyeing and finishing of post-treatment agent. It is used as raw material for acid-making agent in pharmaceutical industry.