A hard water sample contains 0.0081 %Ca by mass (in the form of Ca2+ ions)What mass of water in grams contains 1.3g of Ca?

(1.3g of Ca is the recommended daily allowance of calcium for 19- to 24-year-olds.)

Need help set this up?

1 answer

1.3 = .000081x
x = 16049.38

So, subtract the 1.3g from that