A hard water sample contains dissolved Mg(HCO_3)_2only. If degree of hardness of that sample is 150ppm, calculate the weight of Mg(HCO_3)_2present in 1kg of water sample.

A hard water sample contains dissolved Mg(HCO_3)_2only. If degree of h

1.	A hard water sample contains dissolved Mg(HCO_3)_2only. If degree of hardness of that sample is 150ppm, calculate the weight of Mg(HCO_3)_2present in 1kg of water sample.
Answer» Solution :Degree of hardness is 150ppm. It means that `10^6`G of WATER sample contains 150 g of `CaCO_3`(which is equivalent to `Mg(HCO_3)_2` . Weight of `CaCO_3`in 1KG `(10^3 g)` of water `= (10^3 xx 150)/(10^6) =0.15 g ` 0.15 g of `CaCO_3 -= 0.219 g ` of `Mg(HCO_3)_2` 0.15 g of `CaCO_3 -= (146 xx 0.15)/(100)` `= 0.219g Mg (HCO_3)_2` Weight of `Mg(HCO_3)_2`present in 1kg of water = 0.219 gram