**Calculating Calcium Hardness as CaCO3**

The hardness (in mg/L as CaCO3) for any given metallic ion is calculated using Equation

Calcium hardness (m/L) as CaCO3/equivalent weight of CaCO3

**=** Calcium (mg/L)/equivalent weight of calcium

Example:-

A water sample has calcium content of 51 mg/L. What is this calcium hardness expressed as CaCO3?

Solution

Referring to Equation:

x mg/L /50.045=51 mg/L [....]