1 Water quality of a river Constituent Calcium Ca Magnesium

1. Water quality of a river: Constituent Calcium (Ca Magnesium (M Sodium (Na) Potassium (K Iron (Fe Bicarbonate (HCO3 Sulfate (SO4 Nitrate (NO3 Concentration (m 3.5 3.3 0.12 19 0.2 H 6.7 Determine a) Calcium and magnesium hardness expressed as meq/L and as mg/L equivalent CaCOa b) The total hardness as meq/L and as mg/L equivalent CaCO3 c) The alkalinity as meq/L and as mg/L equivalent CaCO3 d) Nitrate as nitrogen (N) in mg/L

Solution

Solution:-

1. Calcium hardness = Ca⁺⁺ in mg/l x combined weight of CaCO₃/(combined weight of Ca⁺⁺)

                                     =11 x 50/20 =27.5 mg/l

In meq/l =27.5/20 =1.375 meq/l

Magnisium hardness = Mg⁺⁺ in mg/l x combined weight of CaCO₃/(combined weight of Mg⁺⁺)

                                        =3.5 x 50/12 =14.58 mg/l

In meq/l =14.58/12 =1.215 meq/l

2. Total hardness = 27.5 +14.58 =42.08 mg/l

In meq/l =1.375+ 1.215 = 2.59 meq/l

3. Alkalinity =HCO₃^- as CaCO₃

                       = 22 x50 /61 =18.03 mg/l

In meq/l =18.03/61 = 0.295

4. Nitrate = (0.2 x Nitrogen /3)/62

                   = (0.2 x 14/3)/62 = 0.0150 mg/l

In meq/l =.0150/62 = 0.00024 answer