Aabsolute ethanol

Absolute ethanol is a colorless, transparent, volatile, flammable, non-conductive liquid. It has the smell of wine and a pungent spicy taste, slightly sweet. The scientific name is ethanol, the molecular formula C2H5OH, because its chemical formula contains hydroxyl groups, so It is called ethanol and has a specific gravity of 0.7893 (20/4°). The freezing point is -117.3°C. The boiling point is 78.2°C. It is miscible with water, methanol, ether and chloroform in any ratio. It is hygroscopic. It can form an azeotropic mixture with water. Boiling point 78.15℃. Mixture of ethanol vapor and air can cause an explosion. The explosion limit concentration is 3.5-18.0% (W). Alcohol at 70% (V) has a strong killing effect on bacteria. It can also be used as a preservative, solvent, etc. Ethanol in the critical state (243℃, 60kg/CM·CM) has a very strong dissolving ability, and can achieve supercritical quenching. Because its freezing point of the solution drops, it must be Concentrated alcohol solution can be used as antifreeze and refrigerant. Alcohol can replace gasoline as fuel and is a renewable energy source.

100% ethanol

When preparing absolute ethanol in the laboratory, add fresh lime to 95.57% of the alcohol and heat it to reflux, so that the water in the alcohol reacts with calcium oxide to form non-volatile calcium hydroxide to remove the water. Then distill again, so that 99.8% anhydrous alcohol can be obtained, boiling point 78.5 ℃. If you want to prepare absolutely anhydrous alcohol, you can distill it by adding benzene in 95.57% of the alcohol. Because the boiling point of the mixed liquid of 18.4% ethanol, 74.1% benzene and 7.4% water is lower than that of these three pure liquids, it is 65°C. The fraction collected at this time is a mixture of ethanol, benzene and water, all of which can be distilled off. The fraction collected later at 78.5°C is absolutely 100% ethanol.