Cadmium sulfate

Cadmium sulfate
Names
	IUPAC name Cadmium(II) sulfate
	Other names Sulfuric acid, cadmium salt (1:1),
Identifiers
CAS Number	10124-36-4 ; 7790-84-3 (octahydrate) ; 13477-21-9 (tetrahydrate) ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:50292 ; CHEBI:86157 (octahydrate);
ChemSpider	23335 ;
ECHA InfoCard	100.030.288
EC Number	233-331-6;
Gmelin Reference	8295
PubChem CID	24962 (anhydrous); 23618914 (tetrahydrate); 16211218 (octahydrate);
RTECS number	EV2700000;
UNII	947UNF3Z6O ;
UN number	2570
CompTox Dashboard (EPA)	DTXSID1020229 ;
	InChI InChI=1S/Cd.H2O4S/c;1-5(2,3)4/h;(H2,1,2,3,4)/q+2;/p-2 Key: QCUOBSQYDGUHHT-UHFFFAOYSA-L ; InChI=1/Cd.H2O4S/c;1-5(2,3)4/h;(H2,1,2,3,4)/q+2;/p-2 Key: QCUOBSQYDGUHHT-NUQVWONBAG;
	SMILES [Cd+2].[O-]S([O-])(=O)=O;
Properties
Chemical formula	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);
Melting point	1,000 °C (1,830 °F; 1,270 K) (anhydrous); 105 °C (221 °F; 378 K) (monohydrate, decomposes); 40 °C (104 °F; 313 K) (octahydrate, decomposes);
Boiling point	(decomposes to basic sulfate and then oxide)
Solubility in water	anhydrous:; 75 g/100 mL (0 °C (32 °F; 273 K)); 76.4 g/100 mL (25 °C (77 °F; 298 K)); 58.4 g/100 mL (99 °C (210 °F; 372 K)); ; ; monohydrate:; 76.7 g/100 mL (25 °C (77 °F; 298 K)); ; ; octahydrate:; very soluble; ;
Solubility in methanol	slightly soluble
Solubility in ethyl acetate	slightly soluble
Magnetic susceptibility (χ)	−59.2×10−6 cm3/mol
Refractive index (nD)	1.565
Viscosity	2.41 mPa·s (20 °C (68 °F; 293 K)); 1.49 mPa·s (40 °C (104 °F; 313 K));
Structure
Crystal structure	orthorhombic (anhydrous); monoclinic (mono & octahydrate);
Thermochemistry
Std molar; entropy (S⦵298)	123 J⋅mol−1·K-1
Std enthalpy of; formation (ΔfH⦵298)	−935 kJ⋅mol−1
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H330, H340, H350, H360, H372, H410
Precautionary statements	P201, P202, P260, P264, P270, P271, P273, P280, P284, P301+P310+P330, P304+P340+P310, P308+P313, P403+P233, P405, P501
NFPA 704 (fire diamond)	3 1 1
Threshold limit value (TLV)	0.01 mg/m3 (total dust); 0.002 mg/m3 (respirable dust); (TWA)
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	107 mg/kg (oral, rat, analgous compound)
LC50 (median concentration)	0.75 mg/L (goldfish, analgous compound)
	NIOSH (US health exposure limits):
PEL (Permissible)	TWA 0.005 mg/m3 (as Cd)
REL (Recommended)	TWA 0.005 mg/m3 (as Cd)
IDLH (Immediate danger)	9 mg/m3 (as Cd)
Safety data sheet (SDS)	Fisher Scientific; Sigma-Aldrich;
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). verify (what is ?) 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: the octahydrate (3CdSO₄·8H₂O) and the anhydrous salt (CdSO₄). All salts are colourless and highly soluble in water.

Preparation

Cadmium sulfate hydrate 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 can be prepared using sodium persulfate:

Cd + Na₂S₂O₈ → CdSO₄ + Na₂SO₄

Applications

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.

Structure

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.^[7]

Occurrence

Cadmium sulfates occur as the following rare minerals drobecite (CdSO₄·4H₂O), voudourisite (monohydrate), and lazaridisite (the octahydrate).

Safety

Cadmium sulfate (along with cadmium and its compounds) are classified as group 1 (human carcinogens) by IARC and have been identified as causing lung and prostate cancer as well as mutagenic effects in humans.^[8]

References

^ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0487-3.
^ ^a ^b Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A21. ISBN 978-0-618-94690-7.
^ ^a ^b "Safety Data Sheet - Cadmium Sulfate". fishersci.com. ThermoFisher Scientific. 28 December 2021. p. 3. Retrieved 21 October 2025.
^ ^a ^b "Safety Data Sheet - Cadmium Sulfate". sigmaaldrich.com. Sigma-Aldrich. 20 May 2025. Retrieved 21 October 2025.
^ "NIOSH Pocket Guide to Chemical Hazards".
^ Aurivillius, Karin; Stålhandske, Claes (1980). "A Reinvestigation of the Crystal Structures of HgSO₄ and CdSO₄". Zeitschrift für Kristallographie - Crystalline Materials. 153 (1–2): 121–129. Bibcode:1980ZK....153..121A. doi:10.1524/zkri.1980.0011.
^ Theppitak, C.; Chainok, K. (2015). "Crystal Structure of CdSO₄(H₂O): A Redetermination"". Acta Crystallographica Section E. 71 (10): i8 – pi9. doi:10.1107/S2056989015016904. PMC 4647421. PMID 26594423.
^ "Cadmium". Beryllium, Cadmium, Mercury, and Exposures in the Glass Manufacturing Industry (PDF). Lyon, France: World Health Organization - International Agency for Research on Cancer. February 1993. p. 210. ISBN 92-832-1258-4. ISSN 0250-9555. Retrieved 21 October 2025.

[1] Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, Florida: CRC Press. ISBN 0-8493-0487-3.

[b1-2] Zumdahl, Steven S. (2009). Chemical Principles 6th Ed. Houghton Mifflin Company. p. A21. ISBN 978-0-618-94690-7.

[FisherSDS-3] "Safety Data Sheet - Cadmium Sulfate". fishersci.com. ThermoFisher Scientific. 28 December 2021. p. 3. Retrieved 21 October 2025.

[AldrichSDS-4] "Safety Data Sheet - Cadmium Sulfate". sigmaaldrich.com. Sigma-Aldrich. 20 May 2025. Retrieved 21 October 2025.

[5] "NIOSH Pocket Guide to Chemical Hazards".

[6] Aurivillius, Karin; Stålhandske, Claes (1980). "A Reinvestigation of the Crystal Structures of HgSO₄ and CdSO₄". Zeitschrift für Kristallographie - Crystalline Materials. 153 (1–2): 121–129. Bibcode:1980ZK....153..121A. doi:10.1524/zkri.1980.0011.

[7] Theppitak, C.; Chainok, K. (2015). "Crystal Structure of CdSO₄(H₂O): A Redetermination"". Acta Crystallographica Section E. 71 (10): i8 – pi9. doi:10.1107/S2056989015016904. PMC 4647421. PMID 26594423.

[8] "Cadmium". Beryllium, Cadmium, Mercury, and Exposures in the Glass Manufacturing Industry (PDF). Lyon, France: World Health Organization - International Agency for Research on Cancer. February 1993. p. 210. ISBN 92-832-1258-4. ISSN 0250-9555. Retrieved 21 October 2025.

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Cadmium compounds
Cadmium(I)	Cd₂(AlCl₄)₂
Cadmium(II)	Cd(BF₄)₂ CdF₂ CdCl₂ CdBr₂ CdI₂ Cd(CN)₂ CdH₂ CdO CdS CdSe CdTe Cd(OH)₂ Cd₃N₂ Cd(NO₃)₂ CdSO₄ CdSeO₄ CdCrO₄ CdWO₄ CdTeO₃ Cd(C₃H₅O₃)₂ Cd₃As₂ Cd₃P₂ Cd₃(PO₄)₂ CsCdCl₃ CsCdBr₃ Cd(CH₃CO₂)₂ Cd(O₂CC₁₇H₃₅)₂