Buffering capacity

Definition

A buffer resists pH movement by supplying chemical species that consume added acid or base before hydrogen concentration swings wildly. pH itself is not a buffer; it only measures where equilibrium currently sits.

A high-pH solution can have very little reserve capacity and collapse the moment acid is added, while a lower-pH solution with strong buffering may absorb a large acid dose with little pH movement. This distinction matters constantly in the field, separating intensity from capacity. Real buffering comes from weak acids and their conjugate bases, most importantly the carbonate system.

Related concepts

Carbonate system shift with pH · pH as equilibrium position · Alkalinity buffering

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Part of The Blueprint of Water · 🧪 chemistry