Water → Tricalcium Phosphate

Participants

Reaction Steps

An aqueous solution of 8.51 g 50 wt % H3PO2 was combined with 8.00 g of 25.0 wt % aqueous solution of calcium acetate monohydrate, Ca(O2CCH3)2.H2O (ACS reagent, Aldrich Chemical Co., Inc. #40,285-0, CAS 5743-26-0), equivalent to 5.69 wt % Ca, to give a clear, colorless solution contained in a 250 ml Pyrex beaker. To this solution was added 20.17 g Ca(NO3)24H2O salt. The molar ratio of Ca/phosphate in this mixture was 3/2 and the equivalent solids level [as Ca3(PO4)2] was 27.3 wt %. Endothermic dissolution of the calcium nitrate tetrahydrate salt proceeded giving a homogeneous solution once the sample warmed to room temperature. Further warming of this solution to >25° C. on a hotplate initiated a reaction which proceeded as described in Example 1. After approximately three minutes, the reaction was essentially complete leaving a moist, white, crumbly solid which was hot to the touch and which smelled of acetic acid. After cooling to room temperature, the solid was stored in a polyethylene vial.

Provenance & Evidence