What is the hardness of a water sample ( in terms of equivalents of CaCO 3 ) containing 10 - 3 M   CaSO 4 ? ( Molar mass of CaSO 4 = 136   g    mol - 1 )

Step-by-step solution

As 1   L solution have 10 - 3   mol   CaSO 4 Eq .    of   CaSO 4 = eq .    of   CaCO 3 In 1   L solution n CaSO 4 × v . f = n CaCO 3 × v . f . 10 - 3 × 2 = n CaCO 3 × 2 n CaCO 3 = 10 - 3   mol   in   1   L ∴ W CaCO 3 = 100 × 10 - 3 g    in 1   L solution ∴ hardness in terms of CaCO 3 = W CaCO 2 W total × 10 6 = 100 × 10 - 3   g 1000   g × 10 6 = 100   p