PHOSPHORUS

PRODUCT IDENTIFICATION

CAS NO.

7723-14-0

PHOSPHORUS

EINECS NO. 231-768-7
FORMULA P4
MOL WT. 123.88

H.S.CODE

2804.70
TOXICITY Oral rat LD50: 3030 ug/kg
SYNONYMS Phosphorus (white); Phosphorous yellow; Phosphorus (red);
Black Phosphorus; Fosforo Bianco (Italian); Gelber Phosphor (German); Phosphore Blanc (French); Phosphorous (White); P Tetrafosfor (Dutch); Tetraphosphor (German); Violet Phosphorus; Weiss Phosphor (German);
SMILES
 

CLASSIFICATION

 

GENERAL DESCRIPTION

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.

PHYSICAL AND CHEMICAL PROPERTIES

PHYSICAL STATE a number of allotropic forms
MELTING POINT 44 C (white), 590 C (red)
BOILING POINT 280 C (white), sublimes (red)
SPECIFIC GRAVITY 1.82 (white), 2.34 (red), 2.70 (black)
SOLUBILITY IN WATER insoluble
pH  
VISCOSITY  
VAPOR DENSITY  

AUTOIGNITION

 

NFPA RATINGS

Health: 3 Flammability: 0 Reactivity: 1

REFRACTIVE INDEX

 
FLASH POINT

30 C(white), 260 C(red)

STABILITY Stable under ordinary conditions

APPLICATIONS

Phosphoric acid, sodium phosphates, calcium, ammonium and potassium phosphates, phosphorus trichloride, pentasulfide and pentoxide.
SALES SPECIFICATION

WHITE/YELLOW PHOSPHORUS

APPEARANCE

white to straw yellow waxy solid

ASSAY

99.0% min

INSOLUBLES IN DILUTE NITRIC ACID

0.1% max

ACIDITY (H3PO4)

0.2% max

SULFUR

0.1% max

RED PHOSPHORUS

APPEARANCE

red to violet amorphosus powder

ASSAY

98.5% min

SOLUBLES IN WATER

1.0%  max

WHITE PHOSPHORUS

0.003% max

MOISTURE

0.25% max

ACIDITY (H3PO4)

0.1% max

TRANSPORTATION

PACKING

250kgs in drum (white), 50kgs in drum (red)

HAZARD CLASS 4.2, 4.1
UN NO. 1381 (yellow), 1338 (red)
OTHER INFORMATION