What are the inspection methods for the purity of industrial alcohol?

(1) specific gravity method, by measuring the specific gravity of liquid, the purity of industrial alcohol to be tested can be obtained.

(2) Wall hanging method: Fill the industrial alcohol to be tested with a dry beaker or test tube, and then pour it out. See if there is liquid hanging on the device wall. If there is, the purity is above 72%, and the more hanging walls, the higher the purity.

(3) combustion method, that is, the industrial alcohol to be tested is used for combustion test; You can get a general idea of its purity.

(4) Combustion sound method, that is, burning with alcohol and listening to the combustion sound. If there is no sound, the purity is high. If there is sound, the alcohol contains excessive water (water that cannot form azeotrope with ethanol); The louder the sound, the lower the purity.

(5) Inverted cold beaker method. When burning, put the cold beaker upside down above the flame, and look at the amount of water drops on the cup wall to know the purity of alcohol. Soak the cotton rope upward, and put the dry cotton rope into the alcohol to be tested. After a period of time, if there are bubbles on the rope, it means that the alcohol purity is low. The more bubbles, the lower the purity.