pOH

Definition

pOH is the negative base-ten logarithm of hydroxide concentration, defined just like pH but for the hydroxide ion. It is given by pOH = -log10[OH-].

Because the product of the two concentrations is constant, the sum of their negative logs is constant too. Knowing pH lets you compute pOH and therefore the hydroxide concentration. For example pH 3 gives pOH 11 and pH 10 gives pOH 4.

Related concepts

pH plus pOH equals 14 · Self-ionization constant of water · pH definition formula

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Part of The Blueprint of Water · 📏 measurement