Calcium Arsenide Property

EPA Substance Registry System

Calcium arsenide (Ca3As2) (12255-53-7)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

Precautionary statements

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P332+P313IF SKIN irritation occurs: Get medical advice/attention.

P337+P313IF eye irritation persists: Get medical advice/attention.

Calcium Arsenide Chemical Properties,Usage,Production

Description

Calcium arsenide has the molecular formula of Ca3As2 and the molecular weight of 270.0772 g/mol. It may be prepared by reacting the elements together.
Since As sublimes at 614°C and Ca melts at 839°C, the latter is melted at about 875°C in an inert atmosphere like argon (not N2 which would form nitrides) and arsenic vapors are carried into the reaction zone by a stream of Ar gas:
3Ca + 2As + heat ? Ca3As2
Its CAS number is 12255-53-7. The standard Gibbs energies of formation of Ca3As2 was determined by a chemical equilibration technique yielding the following results:
3Ca + 2As ? Ca3As2 (solid)
△G°= -723,800 + 172.8T (J/mol)
(T = 1273 to 1573 K)
Calcium arsenide has the zinc-blende (cubic) structure with a = 6.751 ? . It can also be prepared by the reduction of calcium arsenate by carbon:
2Ca3AsO4 + 5C + heat ? Ca3As2 + 2CaO + 3CO2