Alum can be used to wash your face, but long-term use is not recommended.

Alum is a colorless, transparent, lumpy or crystalline powder, odorless and non-toxic, slightly sweet and astringent taste, astringent, easily soluble in water, aqueous solution is acidic, easy to lose the water of crystallization when heated and become a white powder.

The main uses of alum: light chemical industry: water purification, paper sizing, paint printing and dyeing, color pigment pharmaceuticals. Also used in paint, tanning, fiberboard processing, film fixing film, as well as for rubber and metallurgy, colored glass and other industries.

The main use can be large particles of cohesion and precipitation purification is a kind of salt, because the face of the nerve skin tissue and feet are different, it is recommended not to use alum to wash, oily skin, it is recommended that do not at home when there are bangs are tied up, a cup of lemon in the morning and evening of the water, with cucumber or seaweed on the face effect is very obvious, are absorbing, it is recommended that anyway, at home, the face is more effective than the wash face.

Expanded Information

Application - Edible Functions

Alum can also be used to simmer mung bean rice, the main role is to make the mung bean easier to be cooked, but it is not recommended to do so because it is not good to control the amount of potentially poisonous can be replaced with edible soda. The first thing you need to do is to use the same amount of alum as you would use in a restaurant.

Alum can also be used in the preparation of aluminum salts, paints, tanning materials, mordant, paper, waterproofing agents.

Water purification: alum dissolved in water ionization produced Al3 +, Al3 + and water ionization produced by the combination of OHˉ generated aluminum hydroxide, aluminum hydroxide colloidal particles with a positive charge, and negatively charged sediment particles meet each other's charge is neutralized. Lost the charge of the colloidal particles, will soon be agglomerated together, the particles more and more large, and finally sank to the bottom of the water. In this way, the water becomes clear and clean.

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