Characteristic
Calcium nitrate, also called Norgessalpeter (Norwegian saltpeter), is an inorganic compound with the formula Ca(NO3)2. This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate.
Chemical formula: Ca(NO3)2
Molar mass:164.088 g/mol (anhydrous) 236.15 g/mol (tetrahydrate)
Appearance:colorless solid hygroscopic
Density:2.504 g/cm3 (anhydrous) 1.896 g/cm3 (tetrahydrate)
Melting point:561 °C (1,042 °F; 834 K) (anhydrous) 42.7 °C (109 °F; 316 K) (tetrahydrate)
Boiling point:decomposes (anhydrous) 132 °C (270 °F; 405 K) (tetrahydrate)
Solubility in water: anhydrous: 1212 g/L (20 °C) 2710 g/L (40 °C)
tetrahydrate: 1050 g/L (0 °C) 1290 g/L (20 °C) 3630 g/L (100 °C)
Solubility:soluble in ammonia almost insoluble in nitric acid
Solubility in ethanol:51.4 g/100 g (20 °C) 62.9 g/100 g (40 °C)
Solubility in methanol:134 g/100 g (10 °C) 144 g/100 g (40 °C) 158 g/100 g (60 °C)
Solubility in acetone:16.8 g/kg (20 °C)
Acidity (pKa):6.0
Magnetic susceptibility (χ):-45.9·10−6 cm3/mol
Crystal structure: cubic (anhydrous) monoclinic (tetrahydrate)
Application
It is mainly used as a component in fertilizers but has other applications.