Calcium carbonate / carbonic equilibrium

Indicative speciation of inorganic carbon between CO₂, HCO₃⁻ and CO₃²⁻ from acid/base capacity (KNK/ZNK) and water pH.

Calcium carbonate / carbonic equilibrium

From KNK/ZNK and actual water pH this calculator estimates how inorganic carbon is split between CO₂, HCO₃⁻ and CO₃²⁻. Values represent instantaneous concentrations at the given pH.

Input data

Actual water pH [–]

Acid capacity to pH 4.5 (KNK 4.5) [mmol/L]

Acid capacity to pH 8.3 (KNK 8.3) [mmol/L]

Base capacity from pH 4.5 (ZNK 4.5) [mmol/L]

Base capacity from pH 8.3 (ZNK 8.3) [mmol/L]

Results

To see results, please enter pH and all KNK/ZNK values.

This calculation is indicative and based on tabulated relations for acid and base capacity (KNK/ZNK). For detailed water treatment design always use full analyses and relevant standards.

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