The ethanol liquid density is 0.789g/cm³, the ethanol gas density is 1.59kg/m³, the relative density (d15.56) is 0.816, and the formula weight (relative molecular mass) is 46.07g/mol. The boiling point is 78.2°C, the flash point at 14°C is closed, and the melting point is -114.3°C. Pure ethanol is a colorless and transparent liquid with a special fragrance and volatile. The physical properties of ethanol are mainly related to the properties of low-carbon linear alcohols. The hydroxyl groups in the molecule can form hydrogen bonds, so ethanol has high viscosity and is not as polar as organic compounds of similar molecular weight. At 20°C, the refractive index of ethanol is 1.3611. Can be miscible with water in any ratio; miscible in most organic solvents such as ether, chloroform, methanol, acetone, glycerin, etc.
The polarity of the hydroxyl group also makes many ionic compounds soluble in ethanol, such as sodium hydroxide, potassium hydroxide, magnesium chloride, calcium chloride, ammonium chloride, ammonium bromide and sodium bromide; but sodium chloride and chloride Potassium is slightly soluble in ethanol. In addition, its non-polar hydrocarbon group allows ethanol to dissolve some non-polar substances, such as most essential oils and many flavor enhancers, color enhancers and pharmaceutical reagents.