Cadmium sulfate

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Cadmium sulfate
Cadmium sulfate
Names
IUPAC name
Cadmium(II) sulfate
Other names
Sulfuric acid, cadmium salt (1:1),
Niedermayrite
Identifiers
10124-36-4 YesY
7709-84-3 (monohydrate) N
15244-35-9 (octahydrate) N
3D model (Jmol) Interactive image
ChEBI CHEBI:50292 YesY
ChemSpider 23335 YesY
ECHA InfoCard 100.030.288
EC Number 233-331-6
RTECS number EV2700000
UNII 947UNF3Z6O YesY
UN number 2570
Properties
CdSO4
CdSO4·H2O (monohydrate)
3CdSO4·8H2O (octahydrate)
Molar mass 208.47 g/mol (anhydrous)
226.490 g/mol (monohydrate)
769.546 g/mol (octahydrate)
Appearance White hygroscopic solid
Odor odorless
Density 4.691 g/cm3 (anhydrous)
3.79 g/cm3 (monohydrate)
3.08 g/cm3 (octahydrate)[1]
Melting point 1,000 °C (1,830 °F; 1,270 K) (anhydrous)
105 °C (monohydrate)
40 °C (octahydrate)
Boiling point (decomposes to basic sulfate and then oxide)
anhydrous:
75 g/100 mL (0 °C)
76.4 g/100 mL (25 °C)
58.4 g/100 mL (99 °C)
monohydrate:
76.7 g/100 mL (25 °C)
octahydrate:
very soluble
Solubility slightly soluble in methanol, ethyl acetate
insoluble in ethanol
-59.2·10−6 cm3/mol
1.565
Structure
orthorhombic (anhydrous)
monoclinic (hepta & octahydrate)
Thermochemistry
123 J·mol−1·K−1[2]
−935 kJ·mol−1[2]
Hazards
Safety data sheet [1]
Carc. Cat. 2
Muta. Cat. 2
Repr. Cat. 2
Very toxic (T+)
Dangerous for the environment (N)
R-phrases R45, R46, R60, R61, R25, R26, R48/23/25, R50/53
S-phrases S53, S45, S60, S61
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Lethal dose or concentration (LD, LC):
280 mg/kg (oral, rat)
US health exposure limits (NIOSH):
PEL (Permissible)
[1910.1027] TWA 0.005 mg/m3 (as Cd)[3]
REL (Recommended)
Ca[3]
IDLH (Immediate danger)
Ca [9 mg/m3 (as Cd)][3]
Related compounds
Other anions
Cadmium acetate,
Cadmium chloride,
Cadmium nitrate
Other cations
Zinc sulfate,
Calcium sulfate,
Magnesium sulfate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YesYN ?)
Infobox references

Cadmium sulfate is the name of a series of related inorganic compounds with the formula CdSO4·xH2O. The most common form is the monohydrate CdSO4·H2O, but two other forms are known CdSO4·8/3H2O and the anhydrous salt (CdSO4). All salts are colourless and highly soluble in water.

Structure, preparation, and occurrence[edit]

X-ray crystallography shows that CdSO4·H2O is a typical coordination polymer. Each Cd2+ center has octahedral coordination geometry, being surrounded by four oxygen centers provided by four sulfate ligands and two oxygen centers from the bridging water ligands.[4]

Cadmium sulfate octohydrate can be prepared by the reaction of cadmium metal or its oxide or hydroxide with dilute sulfuric acid:

CdO + H2SO4 → CdSO4 + H2O
Cd + H2SO4 → CdSO4 + H2

The anhydrous material is prepared using sodium persulfate:

Cd + Na2S2O8 → CdSO4 + Na2SO4

Cadmium sulfate occurs as the very rare mineral drobecite (CdSO4·4H2O).

Applications[edit]

Cadmium sulfate is used widely for the electroplating of cadmium in electronic circuits. It is also a precursor to cadmium-based pigment such as cadmium sulfide. It is also used for electrolyte in a Weston standard cell as well as a pigment in fluorescent screens.

References[edit]

  1. ^ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3. 
  2. ^ a b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A21. ISBN 0-618-94690-X. 
  3. ^ a b c "NIOSH Pocket Guide to Chemical Hazards #0087". National Institute for Occupational Safety and Health (NIOSH). 
  4. ^ Theppitak, C/; Chainok, K. "Crystal structure of CdSO4(H2O): A Redetermination" Acta Crystallographica, Section E. Structure Reports Online 2015, volume 71, pi8-pi9. Template:Doii