PHOSPHORUS TRIBROMIDE |
PRODUCT
IDENTIFICATION
|
CAS
NO. |
7789-60-8 |
|
EINECS
NO. |
232-178-2 |
FORMULA |
PBr3 |
MOL
WT. |
270.69 |
H.S.CODE
|
2812.90 |
TOXICITY |
|
SYNONYMS |
Phosphorus (III) bromide; Tribromophosphine; |
Phosphoric (III) bromide;
|
SMILES |
phosphorus
with bromide |
CLASSIFICATION
|
|
PHYSICAL AND CHEMICAL PROPERTIES
|
PHYSICAL
STATE |
colourless fuming liquid with irritating odor |
MELTING POINT |
-40
C |
BOILING
POINT |
175
C |
SPECIFIC GRAVITY |
2.88 |
SOLUBILITY
IN WATER |
decomposes |
pH |
|
VISCOSITY |
|
VAPOR DENSITY |
9.3 |
AUTOIGNITION
|
|
NFPA
RATINGS
|
Health: 3 Flammability: 0 Reactivity: 2 Other: water
reactive |
REFRACTIVE
INDEX
|
|
FLASH
POINT |
|
STABILITY |
Stable under ordinary conditions |
GENERAL
DESCRIPTION & APPLICATIONS
|
Phosphorus Tribromide is a colourless fuming liquid with irritating odor;
specific gravity 2.88; melting point -40 C; boiling point 175 C. The liquid
reacts with water rapidly to produce hydrogen bromide and phosphoric acids. It
is prepared by direct union of phosphorus (not excess) with bromine vapour.
(excess contaminates the product with phosphorus(V) bromide). The crude is then
purified by distillation. It reacts readily with hydroxyl groups, which acts as
a bromine atoms provider in many organic chemical synthesis. It is known
that Phosphorus Tribromide is used to prepare pharmaceuticals
such as Alprazolam, Fenoprofen, Methohexital. |
SALES
SPECIFICATION |
APPEARANCE
|
colorless to pale yellow liquid |
ASSAY |
99.0%
min
|
DISTILLATION
RANGE
|
171
- 174 C
|
SPECIFIC
GRAVITY |
2.85
- 2.89
|
TRANSPORTATION
|
PACKING |
|
HAZARD CLASS |
8
(Packing Group: II) |
UN
NO. |
1808 |
OTHER
INFORMATION |
European Hazard
Symbols: C, Risk Phrases: 14-34-37, Safety Phrases: 26-45 |
DESCRIPTION
OF PHOSPHORUS |
Phosphorus is a nonmetallic chemical element in group 15 (nitrogen family,
formerly Va) of periodic table; atomic number 15 atomic mass 30.9738; melting
point ca 44.1 C (white); boiling point ca 280 C (white); specific gravity 1.82
(white), 2.34 (red), 2.70 (black); valence -3, +3, or +5 ; electronic config.
2-8-5 or 1s 22s 22p 63s 23p 3. The phosphorus molecule is composed of four
phosphorus atoms, P4. Phosphorus exists in a number of allotropic forms [white
(alpha and beta), red, black and/or violet] in the same physical state. White
phosphorus is a white to yellow waxy substance which ignites spontaneously in
air to form white fumes of phosphorus pentoxide and glows without emitting heat.
Phosphorus is stored underwater as it is extremely poisonous, insoluble in water
(but soluble in carbon disulfide). Commercial production of elemental phosphorus
is prepared from phosphorite or phosphate rock (apatite, an impure calcium
phosphate mineral) reacting with coke and sand or silica pebblesor at high
temperatures in an electric furnace. Calcium silicate is produced as a
by-product. White phosphorus is used as a deoxidizing agent in the preparation
of steel and phosphor bronze. It is also used in rat poisons and to make smoke
screens (by burning) for warfare. When white phosphorus is heated to about 250 C
with air absence, it changes into the red phosphorus. Red phosphorus, a dark
redish powder or crystal, does not ignite spontaneously unless heated to 200 C,
does not phosphoresce and it is a little less dangerous than white phosphorus.
It is used to make matches. Red phosphorus is prepared commercially by heating
calcium phosphate with sand and coke in an electric furnace. Black allotrope is
obtained industrially by heating at 300 C under pressure with a mercury
catalyst. It has a layer structure and is stable. The major use of phosphorus
compounds is in fertilizers, mainly as a mixture called superphosphate (calcium
hydrogen phosphate), obtained from phosphate minerals by sulfuric acid
treatment; and in nitrophosphates. Phosphorus is burned to make phosphorus
pentoxide [phosphorus(V) oxide], a white solid used as a chlorinating agent in
organic chemistry, as a drying agent and mainly converted to phosphoric acid
used to make phosphates for fertilizers, electro chemical polishing and shaping,
electroplating, metal cleaning and pickling in metal treatment by reaction with
water. Phosphorus is highly reactive. A wide range of compounds is formed for
uses in detergents, water softeners, pharmaceuticals, dentifrices, and in many
other important applications. It forms metal phosphides and covalently bonded
phosphorus(III) and phosphorus(V) compounds. Phosphoric acid can combine with
certain alkaline elements to form salts called phosphates. |
|