Water Hardness (EDTA Method)

Estimate total hardness of water as CaCO₃ in ppm (mg/L) from EDTA titration data.

Volume of EDTA used (mL)

Normality of EDTA (N)

Typically 0.01 N for water hardness.

Volume of water sample (mL)

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ppm as CaCO₃

Total Hardness (ppm) = (V_EDTA × N_EDTA × 50,000) / V_sample

Where 50,000 = equivalent weight of CaCO₃ (50) × 1000 (conversion to ppm).

This calculation assumes that all hardness (Ca²⁺, Mg²⁺) reacts with EDTA in a 1:1 molar ratio.
The result is expressed in parts per million (ppm) of calcium carbonate equivalent.
If you used a different aliquot volume, adjust the sample volume accordingly.
Always record burette readings to two decimal places.