Question

In: Civil Engineering

if the concentration of Mg2+ in water is 36.6 mg/L, what is the hardness of the...

if the concentration of Mg2+ in water is 36.6 mg/L, what is the hardness of the water aa mg/L CaCO3?

Solutions

Expert Solution

Given, concentration of in water = 36.6 mg/L

We know that, hardness is due to the presence of multivalent cations in water and its total concentration will give the hardness of water. is one such cation.

Therefore,

Hardness of water = concentration of

But, we are asked to determine this in terms of mg/L of

This shall be done as follows:

Or

To avoid lengthy calculations we can just multiply given concentration of by a factor of 4.1 to convert it in terms of .

Hence, hardness of water = 150.62 mg/L as CaCO3.


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