半水硫酸钙

Description

calcium sulfate hemihydrate · CAS 10034-76-1 · (CaSO4)2.H2O. UNII 3RW091J48V. Melting Point: 163 °C; Solubility: 0.3 % at 77 °F (NIOSH, 2024); Solubility: (77 °F): 0.3%.

Identification

CAS Registry Number	10034-76-1
PubChem CID	3033839
Molecular formula	(CaSO4)2.H2O
IUPAC name	dicalcium;disulfate;hydrate
UNII (FDA)	3RW091J48V

Computed Descriptors

Molecular Weight	290.3
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	9
Rotatable Bond Count	0
Exact Mass	289.8392057
Monoisotopic Mass	289.8392057
Topological Polar Surface Area	178
Heavy Atom Count	13
Formal Charge	0
Complexity	62.2

Physical & Chemical Properties

Melting Point	163 °C
Solubility	0.3 % at 77 °F (NIOSH, 2024)
Solubility	(77 °F): 0.3%
Density	2.5
Vapor Pressure	0 mmHg (approx) (NIOSH, 2024)
Vapor Pressure	0 mmHg (approx)

Physical description & handling notes

• Plaster of paris appears as white or yellowish, finely divided, odorless powder consisting mostly or entirely of calcium sulfate hemihydrate, CaSO4*1/2H2O. Forms a paste when it is mixed with water that soon hardens into a solid. Used in making casts, molds, and sculpture. Generally non-toxic.
• Large Crystals
• Dry Powder
• White or yellowish, finely divided, odorless powder; [NIOSH]
• FINE HYGROSCOPIC WHITE POWDER.
• White or yellowish, finely divided, odorless powder.

Regulatory Status

GHS notification summary	100% (75 / 75)

GHS Hazard Classification

GHS notification summary	100% (75 / 75)
Reported hazard statements	H335

Documented Uses

• Information on 15 consumer products that contain Calcium sulfate hemihydrate in the following categories is provided:
• Information on 31 consumer products that contain Plaster of paris in the following categories is provided:
• Non-metallic Mineral Product Manufacturing (includes clay, glass, cement, concrete, lime, gypsum, and other non-metallic mineral product manufacturing)
• Materials used in the production of dental bases, restorations, impressions, prostheses, etc.

Synonyms

Calcium sulfate, hemihydrate; RefChem:5639; Calcium sulfate hemihydrate; 10034-76-1; Plaster of paris; Gypsum hemihydrate; 26499-65-0; Crystacal; Densite; Hemihydrate gypsum; Densite (gypsum); dicalcium;disulfate;hydrate; Plaster of Paris (Ca(SO4).1/2H2O); Sulfuric acid, calcium salt, hydrate (2:2:1); calcium sulphate hemihydrate; TA 20

Frequently Asked Questions

What are the CAS number and molecular formula of calcium sulfate hemihydrate?

CAS 10034-76-1; molecular formula (CaSO4)2.H2O; molecular weight — g/mol.

What other names is calcium sulfate hemihydrate known by?

Calcium sulfate, hemihydrate, RefChem:5639, Calcium sulfate hemihydrate, 10034-76-1, Plaster of paris, Gypsum hemihydrate.

Is calcium sulfate hemihydrate classified as hazardous?

100% of GHS notifications report no hazard classification (75 of 75).

What are the key physical properties of calcium sulfate hemihydrate?

Melting Point: 163 °C; Solubility: 0.3 % at 77 °F (NIOSH, 2024); Solubility: (77 °F): 0.3%; Density: 2.5.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.