calcium nitrate

Calcium nitrate
Other names	Kalksalpeter, nitrocalcite, Norwegian saltpeter, lime nitrate
Identifiers
CAS number	10124-37-5 Y, 13477-34-4 (tetrahydrate)
PubChem	24963
UN number	1454
RTECS number	EW2985000
SMILES	[Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O
InChI	1/Ca.2NO3/c;2*2-1(3)4/q+2;2*-1
InChI key	ZCCIPPOKBCJFDN-UHFFFAOYAF
ChemSpider ID	23336
Properties
Molecular formula	Ca(NO3)2
Molar mass	164.088 g/mol (anhydrous) 236.15 (tetrahydrate)
Appearance	colourless
Density	2.504 g/cm3 (anhydrous) 1.896 g/cm3 (tetrahydrate)
Melting point	561 °C (anhydrous) 42.7 °C (tetrahydrate)
Boiling point	decomposes (anhydrous) 132 °C (tetrahydrate)
Solubility in water	anhydrous: 121.2 g/100 mL (20 °C) 271.0 g/100 mL (40° C) tetrahydrate: 102 g/100 mL (0 °C) 129 g/100 mL (20 °C) 363 g/100 mL (100 °C)
Solubility	dissolves in alcohol and acetone
Structure
Crystal structure	cubic (anhydrous) monoclinic (tetrahydrate)
Hazards
MSDS	ICSC 1037
EU Index	Not listed
NFPA 704	0 1 3 OX
Flash point	Non-flammable
Related compounds
Other anions	Calcium sulfate Calcium chloride
Other cations	Magnesium nitrate Strontium nitrate Barium nitrate
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
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. 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.^[1]

Production and reactivity

Norgessalpeter was the first nitrogen fertilizer compound to be manufactured. Production began at Notodden, Norway in 1905. 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:

CaCO₃ + 2 HNO₃ → Ca(NO₃)₂ + CO₂ + H₂O

It is also a byproduct of the Odda Process for the extraction of calcium phosphate:

Ca₃(PO₄)₂ + 6 HNO₃ + 12 H₂O → 2 H₃PO₄ + 3 Ca(NO₃)₂ + 12 H₂O

Like related alkaline earth metal nitrates (as well as LiNO₃), calcium nitrate decomposes upon heating to release nitrogen dioxide:^[1]

2 Ca(NO₃)₂ → 2 CaO + 4 NO₂ + O₂ ΔH = 369 kJ/mol

Use in fertilizer

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. Formulations lacking ammonia are also known: Ca(NO₃)₂.4H₂O (12.8-0-0 + 18.3%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.

References

1. ^ ^{a b} Wolfgang Laue, Michael Thiemann, Erich Scheibler, Karl Wilhelm Wiegand “Nitrates and Nitrites” in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim.doi:10.1002/14356007.a17_265. Article Online Posting Date: June 15, 2000

External links

• Yara corporate history
• Calcium Nitrate - a Hydroculture Salt