M-alkalinity

Definition

The total acid-neutralizing capacity of water, measured by titration to about pH 4.3, contributed by hydroxide, carbonate, and bicarbonate.

The M titration continues past the phenolphthalein endpoint to about pH 4.3, where bicarbonate is converted to carbonic acid and CO2. It captures the full alkalinity pool and is the value used in the boiler CO2 rule of thumb. Compared against P-alkalinity, it lets the species split be inferred.

Related concepts

CO2 Generation Rule of Thumb · P- and M-alkalinity Titration · Alkalinity

How it connects

• this measures Alkalinity

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Part of The Blueprint of Water · 📏 measurement