SDS Volume (2978)

Volume 66. Ammonium Phosphates, p None

Original Measurements

Farr, T. D.; Willard, J. W.; Hatfield, J. D.; J. Chem. Eng. Data 1972, 17, 313.

Variables:

Room Temp: Composition at 273 K. $\pu{K}$

Prepared by:

J. Eysseltová

Method/Apparatus/Procedure:

A stock solution was prepared by saturating conductivity water with $\ce{(NH4)6P4O13.2H2O}$. Portions of this solution were adjusted with either anhydrous ammonia or the H-form of Amberlite IR-120 resin to a selected pH value and evaporated under vacuum at about 298 K to crystallization. The mixture was then equilibrated in a cold room for 1five days to 48 days. Phosphorus was determined gravimetrically as quinolinium molybdophosphate [1], and nitrogen was determined by distillation of ammonia with $\ce{NaOH}$. The pH was measured, after warming to 298 K, with a conventional meter and a glass electrode.

Source and Purity of Materials:

1. $\ce{(NH4)6P4O13.2H2O}$ of sufficient purity was prepared by a modification of two published procedures [2,3].
2. Conductivity water was used.

Estimated Errors:

Ambient temperature: The only information given is that the temperature was kept constant to within ±0.5 K.

References

¹ Perrin, C. H.; J. Assoc. Offic. Agr. Chemists 41, 758 (1958).
² Griffith, G. J.; J. Inorg. Nucl. Chem. 26, 1381 (1964).
³ Osterheld, R. K.; Langguth, R. P.; J. Phys. Chem. 59, 76 (1955).