Cadmium nitrate

Structural formula
General
Surname	Cadmium nitrate
other names	Cadmium (II) nitrate
Molecular formula	Cd (NO 3 ) 2
Brief description	colorless and odorless crystals
External identifiers / databases
ECHA InfoCard	100.030.633
PubChem	25154
Wikidata	Q419670
properties
Molar mass	236.41 g mol −1 (anhydrous)
Physical state	firmly
density	2.46 g cm −3
Melting point	350 ° C (anhydrous); 59.5 ° C (tetrahydrate);
solubility	good in water (1100 g l −1 at 20 ° C)
safety instructions
H and P phrases	H: 301-312-330-340-350-372-410
	P: 201-260-301 + 330 + 331 + 310-304 + 340 + 310-308 + 313-403 + 233-405
Authorization procedure under REACH	particularly worrying : carcinogenic, mutagenic ( CMR ), serious effects on human health are considered likely
Toxicological data	300 mg kg −1 ( LD 50 , rat , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Cadmium nitrate is a white, hygroscopic solid with an unpleasant odor. The substance occurs in various hydrates or anhydrous. Like other cadmium compounds , cadmium nitrate is suspected of being carcinogenic.

Manufacturing

Cadmium nitrate can be produced by dissolving cadmium, cadmium oxide (CdO) or cadmium hydroxide (Cd (OH) ₂ ) in nitric acid and then crystallizing it.

{\ displaystyle \ mathrm {3 \ Cd + 8 \ HNO_ {3} \ longrightarrow \ 3 \ Cd (NO_ {3}) _ {2} + \ 4 \ H_ {2} O + \ 2 \ NO \ uparrow}}

{\ displaystyle \ mathrm {Cd (OH) _ {2} +2 \ HNO_ {3} \ \ longrightarrow \ Cd (NO_ {3}) _ {2} + \ 2 \ H_ {2} O}}

{\ displaystyle \ mathrm {CdO + 2 \ HNO_ {3} \ \ longrightarrow \ Cd (NO_ {3}) _ {2} + H_ {2} O}}

properties

Cadmium nitrate is a white solid which, compared to many other cadmium compounds, is easily soluble in water. Four different hydrates with different amounts of water of crystallization are known which are stable in different temperature ranges. The nonahydrate Cd (NO ₃ ) ₂ · 9 H ₂ O is most stable between −16 and 3.5 ° C, and the tetrahydrate Cd (NO ₃ ) ₂ · 4 H ₂ O between 3.5 and 48.7 ° C. At 48.7 ° C, this gives off two equivalents of water; the dihydrate Cd (NO ₃ ) ₂ · 2 H ₂ O is stable up to 56.8 ° C. Above this temperature, cadmium nitrate is anhydrous. Anhydrous cadmium nitrate decomposes in the heat to cadmium oxide and nitrous gases . It has an orthorhombic crystal structure with the space group Pca 2 ₁ (space group no. 29) and the lattice parameters a = 7.507 Å , b = 15.37 Å and c = 7.507 Å. The tetrahydrate also crystallizes orthorhombically, space group Fdd 2 (No. 43) , a = 5.828 Å, b = 25.86 Å, c = 11.00 Å. Template: room group / 29 Template: room group / 43

use

Cadmium nitrate is used in glass and porcelain production to create a pearly luster . It is also used to extract other cadmium compounds and to manufacture nickel-cadmium batteries .

safety instructions

At the proposal of the Swedish Chemicals Agency, the chemical classification of cadmium nitrate was revised in 2015. On December 4th, the Committee for Risk Assessment (RAC) of the European Chemicals Agency (ECHA) changed the classification for cadmium nitrate as follows: Cadmium nitrate is classified as carcinogenic Carc 1B, mutagenic Muta 1B and STOT RE 1, the additional warnings have been set to H 340 , H350 and H372 (kidney, bone). This classification of the RAC has yet to be implemented by the EU Commission into applicable law, but with the publication it represents the state of knowledge that must be taken into account by companies and authorities.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on cadmium nitrate in the GESTIS substance database of the IFA , accessed on January 9, 2019(JavaScript required) .
↑ Entry on cadmium nitrate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 15, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .
↑ Entry in the SVHC list of the European Chemicals Agency , accessed on January 19, 2018.
^ ^A ^b ^c Karl-Heinz Schulte-Schrepping, Magnus Piscator: Cadmium and Cadmium compounds . In: Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim 2002, doi : 10.1002 / 14356007.a04_499 .
↑ M. Louer, D. Louer, D. Grandjean: Structure cristalline et polymorphisme du nitrate de cadmium anhydre. In: Journal of Solid State Chemistry , 17 (3), 176, pp. 231-237, doi: 10.1016 / 0022-4596 (76) 90127-4 .
↑ B. Matkovic, B. Ribar, B. Zelenko, SW Peterson: Refinement of the Structure of Cd (NO ₃ ) ₂ · 4 H ₂ O. In: Acta Crystallographica , 21, 1966, pp. 719-725, doi: 10.1107 / S0365110X66003773 .
↑ Cadmium Nitrate . In: Römpp Chemie-Lexikon : Thieme Verlag, as of March 2002.
↑ RAC decision of December 4, 2015

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on cadmium nitrate in the GESTIS substance database of the IFA , accessed on January 9, 2019(JavaScript required) .

[CLP_100.030.633-2] Entry on cadmium nitrate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 15, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

[SVHC-3] Entry in the SVHC list of the European Chemicals Agency , accessed on January 19, 2018.

[ullmann-4] A ^b ^c Karl-Heinz Schulte-Schrepping, Magnus Piscator: Cadmium and Cadmium compounds . In: Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim 2002, doi : 10.1002 / 14356007.a04_499 .

[5] M. Louer, D. Louer, D. Grandjean: Structure cristalline et polymorphisme du nitrate de cadmium anhydre. In: Journal of Solid State Chemistry , 17 (3), 176, pp. 231-237, doi: 10.1016 / 0022-4596 (76) 90127-4 .

[6] B. Matkovic, B. Ribar, B. Zelenko, SW Peterson: Refinement of the Structure of Cd (NO ₃ ) ₂ · 4 H ₂ O. In: Acta Crystallographica , 21, 1966, pp. 719-725, doi: 10.1107 / S0365110X66003773 .

[7] Cadmium Nitrate . In: Römpp Chemie-Lexikon : Thieme Verlag, as of March 2002.

[8] RAC decision of December 4, 2015