... .96; Formula wt, dihydrate 177.993,CAS: anhydrous [7558-79-4]; CAS: dihydrate [10028-24-7]5,Specificity: Colorless crystal, easily ... indexFCC-VE339(ii)pH of a 1 % solution--8.4—9.6Content(as dry base),≥%98.098.0 P2O5 Content(Anhydrous basis) ,%--49 ... ≤5.0%,2,Dihydrate ≤22.0%3,Heptahydrate ≤50.0%4,Dodecahydrate ≤61.0%(40°C,3h then 105°C,5h ...