Calcium ion concentration from hardness

Converts calcium hardness expressed as calcium carbonate into actual calcium ion concentration, using the molar masses of CaCO3 (100) and Ca (40).

$$[{\text{Ca}}^{2+}]=\frac{{\text{Ca hardness as CaCO}}_3}{100}\times 40$$

Variables

Symbol	Meaning	Unit
$[{\text{Ca}}^{2+}]$	Calcium ion concentration	mg/L as Ca2+
${\text{Ca hardness as CaCO}}_3$	Calcium hardness expressed as calcium carbonate	mg/L as CaCO3

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Part of The Blueprint of Water