Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Calcium is a soft, gray/silvery alkaline earth metal. It is the lightest of the alkali earth metals with a density of 1.54 g/cm3. It is also the fifth most abundant element by mass in the earth's crust. However, due to its reactivity it is not naturally found in its elemental state. When exposed to air it rapidly forms oxide (CaO) and nitride (Ca2N3). Ca-metal reacts with water, evolving hydrogen gas. In powdered form the reaction with water is extremely rapid. In the Ca-water reaction calcium dihydroxide (Ca(OH)2) is formed. In accordance with Annex VI to Regulation (EC) No 1272/2008 (lists of harmonised classification and labelling), calcium has been classified as follows: Hazard class and category codes: Water React. Flam. Gas 2 (highly flammable and water reactive substance, which violently reacts with water forming flammable gas).