Description
Calcium phosphide has the molecular formula of
Ca3P2 and the molecular weight of 182.1825 g/mol. Its
CAS number is 1305-99-3. It is a red-brown crystalline
material with a melting point of 1605°C. Its density is
2.51 g/cm
3. It readily reacts with water to form phosphine,
PH3, but is insoluble in ethanol.
It is easily prepared by reacting the metal with red
phosphorus at high temperature. The best way is to
sublime the P4 at 450°C in an inert gas stream and react
it with Mg metal at 750°C:
6Ca + 2P4?2Ca3P4
Chemical Properties
Calcium phosphide is a gray granular solid or
reddish-brown crystalline solid. It has a musty odor, somewhat like acetylene.
Uses
For signal fires; in purification of Cu and Cu alloys; as rodenticide.
Uses
Metal phosphides, primarily Ca3P2, have been used
as rodenticides. Calcium phosphide baits have strong,
pungent garlic-like odor characteristic for phosphine
liberated by hydrolysis. The odor attracts rodents, but
has a repulsive effect on other animals, who are not
receptive to the smell. This salt has uses in incendiary
bombs and other explosives. On contact with acids or
water, calcium phosphide releases phosphine, which
ignites spontaneously. It is also used in fireworks, torpedoes,
self-igniting naval pyrotechnic flares, and various
water-activated ammunition.
General Description
CALCIUM PHOSPHIDE appears as red-brown crystals to gray granular lumps. CALCIUM PHOSPHIDE reacts with water to form calcium hydroxide and phosphine, a flammable poisonous gas. Phosphine will normally ignite spontaneously in contact with air. If there is an excess of water this fire of phosphine will not normally ignite surrounding combustible material.
Reactivity Profile
CALCIUM PHOSPHIDE and hydrochloric acid undergo a very energetic reaction [Mellor 8:841 1946-47]. Calcium and other alkaline earth phosphides incandesce in oxygen when heated.
Hazard
Dangerous fire risk; decomposed by water
to phosphine, which is highly toxic and flammable.
See phosphine.
Health Hazard
Inhalation or ingestion causes faintness, weakness, nausea, vomiting. External contact with dust causes irritation of eyes and skin.
Fire Hazard
Behavior in Fire: Can cause spontaneous ignition if wet. Contributes dense smoke of phosphoric acid.
Safety Profile
Highly toxic due to
phosphde, which in presence of moisture
emits phosphine. The phosphine may ignite
spontaneously in air. Incandescent reaction
with oxygen at 300°C. Incompatible with
dichlorine oxide. When heated to
decomposition it emits toxic fumes of POx.
See also CALCIUM COMPOUNDS and
PHOSPHIDES.
Potential Exposure
A strong reducing agent. Forms spontaneously combustible phosphine gas in moist air. Contact
with water or acids release phosphine gas, and can cause
explosions. Incompatible with oxidizers (chlorates, nitrates,
peroxides, permanganates, perchlorates, chlorine, bromine,
fluorine, etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong bases, strong acids,
oxoacids, epoxides, chlorine monoxide, halogens, halogen
acids, oxygen, sulfur
First aid
If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seekmedical attention immediately. If this chemical contactsthe skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove fromexposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing hasstopped and CPR if heart action has stopped. Transferpromptly to a medical facility. When this chemical hasbeen swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit.
storage
Color Code—Yellow Stripe (strong reducingagent): Reactivity Hazard; Store separately in an area isolated from flammables, combustibles, or other yellow-codedmaterials. Store in tightly closed containers in a cool,well-ventilated area away from strong oxidizers (such aschlorine, bromine, and fluorine), strong acids (such ashydrochloric, sulfuric, and nitric), oxygen, sulfur, or moisture since violent reactions occur. Sources of ignition, suchas smoking and open flames, are prohibited where Calciumphosphide is handled, used, or stored. Use only nonsparkingtools and equipment, especially when opening and closingcontainers of Calcium phosphide. Wherever Calciumphosphide is used, handled, manufactured, or stored, useexplosion-proof electrical equipment and fittings. Do notstore large amounts of this material in a room protected bywater sprinkler systems. Protect containers against physicaldamage.
Shipping
UN1360 Calcium phosphide, Hazard Class: 4.3;
Labels: 4.3-Dangerous when wet material
Incompatibilities
A strong reducing agent. Forms spontaneously combustible phosphine gas in moist air. Contact
with water or acids release phosphine gas, and can cause
explosions. Incompatible with oxidizers (chlorates, nitrates,
peroxides, permanganates, perchlorates, chlorine, bromine,
fluorine, etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong bases, strong acids,
oxoacids, epoxides, chlorine monoxide, halogens, halogen
acids, oxygen, sulfur
Waste Disposal
Disposal of unused product
must be undertaken by qualified personnel who are
knowledgeable in all applicable regulations and follow all
pertinent safety precautions including the use of appropriate protective equipment. For proper handling and disposal, always comply with federal, state, and local
regulations
