Northerners use brine, and the brine before ordering tofu is poisonous. Yang Bailao in the opera and the movie White-haired Girl committed suicide by drinking salt water. The scientific name of bittern is bittern. Dongying city is rich in brine resources underground. After the brine is boiled, the remaining black liquid is brine, which is a mixture of magnesium chloride, magnesium sulfate and sodium chloride. If you know the name of sodium chloride, you will know why salt water kills people.