Inverse Solubility of Calcium Carbonate

Definition

The property of calcium carbonate by which it precipitates more, not less, as temperature rises.

Unlike most salts, calcium carbonate becomes less soluble in hotter water, so it falls out of solution exactly where water is warmest. This is why scale deposits preferentially on the hottest heat-transfer surfaces and why even trace calcium plates out on boiler tubes. It is the third stacking temperature effect that drives scaling.

Related concepts

Boiler Alkalinity Breakdown · Temperature (Lever) · Calcium Carbonate Scaling

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Part of The Blueprint of Water · 🔥 thermodynamics