Potassium carbonate, white crystalline powder. Density 2.428g/cm3. The melting point is 891°C, it decomposes at the boiling point, and the relative molecular weight is 138.21. Soluble in water, the aqueous solution is alkaline, insoluble in ethanol, acetone and ether. It is highly hygroscopic and can absorb carbon dioxide and moisture when exposed to the air and turn into potassium bicarbonate. It should be sealed and packaged. Hydrates include monohydrate, dihydrate, and trihydrate. Potassium carbonate aqueous solution is alkaline. Insoluble in ethanol and ether.
Physical and chemical properties
Potassium carbonate is available as anhydrous or crystalline product containing 1.5 molecules. The anhydrous product is white granular powder, and the crystalline product is white translucent small crystals or particles. It is odorless and has a strong alkaline smell. The relative density is 2.428 (19°C), the melting point is 891°C, and the solubility in water is 114.5g/l00mL (25°C). ), easily absorb moisture and deliquesce in humid air. Soluble in 1mL water (25℃) and about 0.7mL boiling water. After the saturated aqueous solution is cooled, glassy monoclinic crystal hydrate will precipitate. The relative density is 2.043. It loses crystal water at 100℃. The pH value of 10% aqueous solution is about 11.6 and is insoluble. In ethanol and ether. Added to flour products, it can produce special flavor, color and toughness. This product is an alkaline agent.
Purpose
1. Potassium carbonate can be used in glass, printing and dyeing, soap, enamel, preparation of potassium salts, decarbonylation of synthetic ammonia, and is also used in the color TV industry. It is mainly used as a leavening agent in food.
2. Mainly used for analytical reagents. Such as high purity analysis, emission spectrum analysis, etc. It can also be used as a flux for silicates and insoluble sulfates, a water absorbent for organic liquids, and in the electroplating, fertilizer, and photography industries.
3. Used as a leavening agent in glass, printing and dyeing, soap, enamel, preparation of potassium salts, decarbonylation of synthetic ammonia, color TV industry, food; used as gas adsorbent, dry powder fire extinguishing agent, rubber antioxidant, etc. Processing of exposed photosensitive materials.
4. Used in the manufacture of glass bulbs of picture tubes in the electronic industry, decarburization of fertilizer production, and potassium salt manufacturing. It is used as analytical reagents and fluxes, and is also used in the preparation of various potassium salts; used in analytical reagents, benchmark reagents, and Flux for molten silicates and insoluble sulfates.
5. Use as desiccant in chemical experiments. Its water absorption capacity is medium and it can form potassium carbonate with two crystal waters (K2CO3·2H2O), but it reacts slowly with water. Suitable for drying neutral organic compounds such as alcohols and esters, as well as general alkaline organic compounds such as amines and alkaloids. But it cannot be used as a desiccant for acids, phenols or other acidic substances.
6. Alkaline agent and dough improver, and can inhibit the sourness of noodles. It can be used in pasta products and should be used in appropriate amounts according to production needs. Used in the production of optical glass to improve glass transparency, strength and refractive index.
