ii) The maximum permitted sulfate concentration in water is 250mg dm^-3, 200cm^3 of aqueous BaCl2 is added to 300cm^3 of water at the maximum permitted sulfate level, and a white precipitate formed. Calculate the minimum conc. (mol dm^3)of the BaCl2

250x10^-3= 0.25g dm^-3sulfate mr x moles = mass0.25 x 3/10 = 0.075 g sulfatemr sulfare = 32 + (4 x 16) = 96moles sulfate = 0.075/96 = 7.8125 x10^-4Per equation above: moles SO₄^2-= moles Ba²⁺ Concentration= Moles/Volume[Ba²⁺] = 7.8125x10^-4/0.2=3.91x10^-3 mol dm^-3