Disodium hydrogen phosphate dihydrate
CAS 10028-24-7
A buffer is not one chemical holding pH still; it is a pair of chemical forms continuously exchanging protons.
Disodium hydrogen phosphate dihydrate supplies HPO4^2-, the more basic half of the phosphate buffer pair near neutral pH. Together with H2PO4-, it absorbs small additions of acid or base through reversible proton transfer. The two crystal waters matter when preparing solutions because hydrate and anhydrous forms have different formula weights. A phosphate buffer is an engineered acid-base equilibrium, not merely a neutral salt solution.
Published:
2026-09-10
