There is no specific formula for lemon juice, as this liquid is a mixture and not a singular compound. Lemon juice is made of water, citric acid, vitamins and minerals, each specific compound having its own chemical formula.
Lemon juice is a good source of vitamin C, folate and potassium and is very low in cholesterol and saturated fat. One cup of lemon juice provides 112 milligrams of vitamin C and 31.7 micrograms of folate. Other nutrients and vitamins found in lemon juice include vitamin A, E, B6, thiamine, calcium, magnesium, copper and zinc. Lemon is also the citrus fruit containing the highest amount of citric acid.