2% neutral sodium fluoride contains-
Method of preparation of 2% neutral sodium fluoride:
It is prepared by dissolving 20 grams of sodium fluoride powder in one liter (1000 ml) of distilled  water in a plastic bottle. It is essential to store fluoride in plastic bottles because if stored in glass containers, the fluoride ion of solution can react with silica of glass forming silicon fluoride, thus reducing the availability of free active fluorides for anticaries action.
20 g sodium fluoride powder in 1000 ml distilled water
20 mg sodium fluoride powder in 1000 ml distilled water
20 g sodium fluoride powder in 100 ml distilled water
20 mg sodium fluoride powder in 100 ml distilled water