Silicon dioxide is soluble in water, alkalies and hydrofluoric acid to varying degrees depending on its form. Silicon dioxide is significantly more soluble in water as silica as opposed to as quartz.
Silicon dioxide, also known as quartz, silica, silicic oxide, and crystalline silica, is soluble in water, alkalies, and hydrofluoric acid. Silicon dioxide's chemical formula is SiO2. In the chemical formula, the "Si" represents the element silicon and the "O" represents the element oxygen. Thus, silicon dioxide is made of one silicon molecule and two oxygen molecules.
Silicon dioxide is used in the production of glass for windows and bottles in its silica form. The silica form of silicon dioxide is also used in the production of foods, generally as a flow agent in powdered foods.