  Answer   This depends on what liquid you're measuring. Since every substance has a specific density, the mass of one liter of liquid depends on its density. Using … water as an example, the density of water at 4Co is 1g/ml. So 2 liters of water would weight approximately 2 kg or 4.4 lbs (1 kg = 2.2 lbs).+ 18 others found this useful.onfidence votes 23.6K. One liter of water weighs (nominally) one kilogram. A kilogram is equal to 2.20462 pounds. Therefore, 4.4 k X 2.2 = 9.68 lbs. of water.