What mass of NaCO3 is required to remove 90% of these ionsfrom10.0L of laundry water?
Since soap and detergent action is hindered by hard water,laundryformulations usually include watersofteners-calledbuilders-designed to remove hard water ions(especially Ca2+ andMg2+) from the water. A common builder used inNorth America issodium carbonate. Suppose that the hard water usedto do laundrycontains 75 ppm CaCO3 and 55 ppm MgCO3 (by mass).
