Calcium sulfate, hemihydrate

Description

Fine-grain, odorless powder commonly called Plaster of Paris. Hemihydrate calcium sulfate is made by partially calcining Gypsum. When mixed with water, plaster of Paris will dry to a hard mass. It is used for wall plasters, wallboard, moldings, and statuary.

Synonyms and Related Terms

plaster of Paris; dried calcium sulfate; dried gypsum; plaster;

Composition	CaSO4-0.5H2O
CAS	7778-18-9
Melting Point	163
Density	2.5
Molecular Weight	mol. wt. = 145.15

Hazards and Safety

Ingestion may be harmful.

Mallinckrodt Baker: MSDS

Authority

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 1753