In chemistry, a Alkali is a compound that can ionize hydroxide ions in an aqueous solution, and it can be neutralized with acids to form salts. Alkali has the characteristics of strong ionization, high solubility, corrosion and so on. Sodium hydroxide (NaOH) has many uses. Used in the production of paper, soap, dyes, rayon, smelting metal, petroleum refining, cotton finishing, coal tar products purification, as well as food processing, wood processing and machinery industry, industrial grade potassium hydroxide: used in the production of sodium metal, such as electrolytic sodium metal, etc.