Ethanol is a good solvent that can dissolve many inorganic substances and many organic substances, so ethanol is commonly used to dissolve plant pigments or medicinal ingredients in it, and ethanol is also commonly used as a solvent for the reaction, so that the organic matter and inorganic substances participating in the reaction can be dissolved, increase the contact area, and improve the reaction rate. For example, in the saponification reaction of grease, the addition of ethanol can dissolve both sodium hydroxide and grease, so that they are fully in contact with the homogeneous (solution of the same solvent), speeding up the reaction rate and increasing the reaction limit.
The physical properties of ethanol are mainly related to the properties of its low carbon straight chain alcohols. The hydroxyl groups in the molecule can form hydrogen bonds, so ethanol is very viscous and less polar than organic compounds with similar relative molecular weights. At room temperature, ethanol is a colorless, flammable, volatile liquid with a distinctive flavor.
Colorless and transparent; Flammable and volatile liquid. It has an alcoholic odor and pungent taste. Soluble in water, methanol, ether and chloroform. It can dissolve many organic compounds and some inorganic compounds. It has hygroscopic properties. It forms an azeotrope with water. The vapor and air form an explosive mixture with an explosion limit of 4.3-19.0 (volume). The relative density of anhydrous ethanol is 0.7893 (20/4ºC), the melting point is -117.3ºC, the boiling point is 78.32ºC, the refractive index is 1.3614, and the flash point (closed cup) is 14ºC. Industrial ethanol (including ethanol 95) has refractive index of 1.3651, surface tension (20ºC) 22.8mN/m, viscosity (20ºC) 1.41mPa·s, vapor pressure (20ºC) 5.732kPa, specific heat capacity (23ºC) 2.58J/(g·ºC), flash point of 12.8ºC, relative density of 0.816, boiling point of 78.15ºC. Freezing point -114ºC, spontaneous combustion point 793ºC.