Nitrocalcite

Calcium nitrate

Names
Other names Kalksalpeter, nitrocalcite, Norwegian saltpeter, lime nitrate
Identifiers
CAS Number	10124-37-5 Y 13477-34-4 (tetrahydrate) N
3D model (Jmol)	Interactive image
ChemSpider	23336 Y
ECHA InfoCard	100.030.289
PubChem	24963
RTECS number	EW2985000
UNII	NF52F38N1N N
UN number	1454
InChI InChI=1S/Ca.2NO3/c;2*2-1(3)4/q+2;2*-1 Y Key: ZCCIPPOKBCJFDN-UHFFFAOYSA-N Y InChI=1/Ca.2NO3/c;2*2-1(3)4/q+2;2*-1 Key: ZCCIPPOKBCJFDN-UHFFFAOYAF
SMILES [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O
Properties
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
Structure
Crystal structure	cubic (anhydrous) monoclinic (tetrahydrate)
Hazards
Safety data sheet	ICSC 1037
R-phrases	R22, R41
NFPA 704	0 1 3 OX
Flash point	Non-flammable
Lethal dose or concentration (LD, LC):
LD50 (median dose)	302 mg/kg (rat, oral)
Related compounds
Other anions	Calcium sulfate Calcium chloride
Other cations	Magnesium nitrate Strontium nitrate Barium nitrate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Calcium nitrate, also called Norgessalpeter (Norwegian saltpeter), is the inorganic compound with the formula Ca(NO₃)₂. This colourless salt absorbs moisture from the air and is commonly found as a tetrahydrate. It is mainly used as a component in fertilizers but has other applications. Nitrocalcite is the name for a mineral which is a hydrated calcium nitrate that forms as an efflorescence where manure contacts concrete or limestone in a dry environment as in stables or caverns. A variety of related salts are known including calcium ammonium nitrate decahydrate and calcium potassium nitrate decahydrate.

Norgessalpeter was synthesized at Notodden, Norway in 1905 by the Birkeland–Eyde process. Most of the world's calcium nitrate is now made in Porsgrunn.

It is produced by treating limestone with nitric acid, followed by neutralization with ammonia:

It is also an intermediate product of the Odda Process:

It can also be prepared from an aqueous solution of ammonium nitrate, and calcium hydroxide:

Like related alkaline earth metal nitrates, calcium nitrate decomposes upon heating (starting at 500 °C) to release nitrogen dioxide:

As of 1978, only 170,000 tons/year were produced for applications in fertilizers. The fertilizer grade (15.5-0-0 + 19% Ca) is popular in the greenhouse and hydroponics trades; it contains ammonium nitrate and water, as the "double salt" 5Ca(NO₃)₂.NH₄NO₃·10H₂O. This is called calcium ammonium nitrate. Formulations lacking ammonia are also known: Ca(NO₃)₂·4H₂O (11.9-0-0 + 16.9%Ca). A liquid formulation (9-0-0 + 11% Ca) is also offered. An anhydrous, air-stable derivative is the urea complex Ca(NO₃)₂·4[OC(NH₂)₂], which has been sold as Cal-Urea.