Question

A sample of water is known to contain \(Mg(HCO_3)_2=7.3\ \text{mg/L\), \(Ca(HCO_3)_2=8.1\ \text{mg/L}\), and \(27.2\ \text{mg/L}\) of \(CaSO_4\). The total hardness associated with water sample in ppm in equivalents of \(CaCO_3\) is \[ (\text{At.wt. }H=1,\ C=12,\ O=16,\ Mg=24,\ Ca=40,\ S=32) \] }

• A. \(20\)
• B. \(25\)
• C. \(30\)
• D. \(40\)

Hint:

To convert hardness into \(CaCO_3\) equivalent, use \(\frac{\text{salt amount}\times 50}{\text{equivalent weight of salt}}\).

Answer 1

The Correct Option is C