Question

Calculate the Molar concentration (mmole/L), Valance and Total Dissolved Ions (TDI, meq/L) for a water analysis with the below chemistry sample information below:

Ca: 55mg/L

Mg: 49mg/L

Na: 200mg/L

K: 4.5 mg/L

Cl:324 mg/L

SO4: 18mg/L

HCO3: 291mg/L

NO3: 26mg/L

TDS = 967.5 mg/L

Answer 1

Ca: 55mg/L

40 gm in 1000 mL -1 M

1 mg in 1000 mL- 1/(40 x1000) M

55 mg in 1000 mL- 55/(40 x1000) M = 1.375 x 10^-3 M =1.375 mmoles/L

Mg: 49mg/L

24 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(24 x1000) M

49 mg in 1000 mL = 49/(24 x1000) M = 2.04 x 10^-3 M = 2.04 mmoles/L

Na: 200mg/L

23 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(23 x1000) M

200 mg in 1000 mL = 200/(23 x1000) M = 8.69 x 10^-3 M = 8.69 mmoles/L

K: 4.5 mg/L

39 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(39 x1000) M

4.5 mg in 1000 mL = 4.5/(39 x1000) M = 1.15 x 10^-4 M = 1.15 x 10^-1 mmoles/L

Cl:324 mg/L

35.5 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(35.5 x1000) M

324 mg in 1000 mL = 324/(35.5 x1000) M = 9.12 x 10^-3 M = 9.12mmoles/L

SO₄^2-: 18mg/L

96 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(96 x1000) M

18 mg in 1000 mL = 18/(96 x1000) M = 1.87 x 10^-4 M = 1.87 x 10^-1 mmoles/L

HCO₃^-: 291mg/L

61 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(61 x1000) M

291 mg in 1000 mL = 291/(61 x1000) M = 4.77 x 10^-3 M = 4.77 mmoles/L

NO₃^-: 26mg/L

62 gm in 1000 mL =1 M

1 mg in 1000 mL = 1/(62 x1000) M

26 mg in 1000 mL = 26/(62 x1000) M = 4.19 x 10^-4 M = 4.19 x 10^-1 mmoles/L