A solution is said to contain 38% phosphoric acid by mass. What does this mean? 1 L of this solution contains 38 mL of phosphoric acid the density of this solution is 3.8 g/mL 1L of this solution has a mass of 38 g 1 mol of this solution contains 38 g of phosphoric acid 100 g of this solution contains 38 g of phosphoric acid​