Basic Calcium Nitrates

If calcium hydroxide be added to a saturated solution of calcium nitrate until no more dissolves, the liquid becomes semi-solid after a few minutes and contains crystals of composition Ca(NO₃)₂.Ca(OH)₂.2.5H₂O. The compound loses its water of crystallisation at 160° C., and is decomposed by water. Bassett and Taylor gave the formula as Ca₂N₂O₇.3H₂O, and stated that at 100° C. the hydrates Ca₂N₂O₇.2H₂O and Ca₂N₂O₇.0.5H₂O may be obtained.

Quicklime, when slaked with a concentrated solution of calcium nitrate, gives white needles of the compound 2Ca(OH)₂.Ca(NO₃)₂.2H₂O which become turbid on the addition of water.