Wet the facial skin with warm water first, then rub it on the palm with half a teaspoon of fine salt until it dissolves, and apply it evenly on the face, chin and behind the ears. When rubbing, don't use your fingers too hard to avoid hurting your skin. After massage for 30 seconds, rinse with warm water once. Don't let the salt stay on your face for too long to avoid stinging.

Salt:

Salt refers to sea salt, well salt, mineral salt, lake salt and earth salt from different sources. Their main component is sodium chloride, and the state stipulates that the sodium chloride content of well salt and mineral salt shall not be less than 95%. Salt contains barium salt, chloride, magnesium, lead, arsenic, zinc, sulfate and other impurities.

Sodium chloride, the main component of salt, ionic compound. Pure sodium chloride crystal is a colorless and transparent cubic crystal. Due to the existence of impurities, sodium chloride is generally white cubic crystal or fine-grained powder, with a specific gravity of 2. 165(25/4℃), a melting point of 80 1℃, a boiling point of 1442℃, a density of 2. 165g/cm2, and is salty.

Soluble in water or glycerol, insoluble in ethanol and hydrochloric acid, neutral and conductive in aqueous solution. Solid sodium chloride is not conductive, but molten sodium chloride is conductive. With the increase of temperature, the solubility in water increased slightly.

When the temperature is lower than 0. 15℃, NaCl dihydrate can be obtained. Sodium chloride is abundant in seawater and natural salt lakes, and can be used to produce chlorine, hydrogen, hydrochloric acid, sodium hydroxide, chlorate, hypochlorite, bleaching powder and metallic sodium. It is an important chemical raw material. It can be used for seasoning food and curing fish and vegetables, as well as salting out soap and tanning leather.