Sodium dihydrogen phosphate dihydrate
CAS 13472-35-0
Water in a hydrate is not just moisture; it can be a defined part of the crystal and the formula weight.
Sodium dihydrogen phosphate dihydrate shows why crystal water is part of chemical identity. Two H2O molecules belong to each formula unit, changing molar mass and solid-state behavior. After dissolution, the phosphate enters ordinary buffer equilibria, but before dissolution the dihydrate cannot be substituted gram-for-gram for monohydrate or anhydrous material. Hydration state matters on the balance and in storage.
Published:
2026-09-10
