THE MPU HR SEC SCHOOL PRESENTED BY M.A.MOSES SUSAI NATHAN M.A.MOSES SUSAI NATHAN J.NIJAMUDEEN J.NIJAMUDEEN C.P.SATHISH C.P.SATHISH M.SURENDAR M.SURENDAR M.DHINESH BABU M.DHINESH BABU GUIDED BY C.D.ANURADHA

PHOSPHOROUS

Phosphorous is a non metal placed inVA group of periodic table. Its atomic number is 15.it exhibits valency 3,5.

It glows in dark and to mean the same it has been named phosphorous.

Sources of phosphorous: phosphorous occurs in nature as phosphates. Some of the chief ores of phosphorous are: 1.phosphorite,bone ash ca 3 (po 4 ) 2 2.chlorapatite 3ca 3 (po 4 ) 2 cacl 2

bone ash contains phosphorous in the form of calcium phosphate abundantly. Hence phosphorous is extracted from bone ash. Extraction of phosphorous: bone ash contains phosphorous in the form of calcium phosphate abundantly. Hence phosphorous is extracted from bone ash.

(1)at c,silica from sand reacts with calcium phosphate from bone ash to give phosphorous(v)oxide and calcium silicate. Ca 3 (po 4 ) 2 +3sio 2` Casio 3 +p 2 o 5

Allotropes of phosphorous: An element may exist in various forms which have different physical properties but same chemical properties. This properties is called allotropy and the different forms of element are called allotropes. The important allotropic forms of phosphorous are white phosphorous and red phosphorous

white phosphorous can be converted to red phosphorous by heating white phosphorous in presence of nitrogen to about C with a little iodine as catalyst. Conversion of white phosphorous into red phosphorous: white phosphorous can be converted to red phosphorous by heating white phosphorous in presence of nitrogen to about C with a little iodine as catalyst.

1.white phosphorous is white waxy solid with a smell of garlic and is poisonous. Red phosphorous is odourless non poisonous red powder. 2.the ignition temperature of white phosphorous is 30 0 C hence it can easily catch fire. So it is kept preserved in water. Physical properties: 1.white phosphorous is white waxy solid with a smell of garlic and is poisonous. Red phosphorous is odourless non poisonous red powder. 2.the ignition temperature of white phosphorous is 30 0 C hence it can easily catch fire. So it is kept preserved in water.

Chemical properties : 1.phosphorous burns in air forming whit fumes of phosphorous (v) oxide 4p+5o 2 2p 2 o 5 2.whit phosphorous evolves phosphine (ph 3 ) on warming with a strong solution of caustic soda(sodium hydroxide) 4p+3naoh+3h 2 oph 3 +3nah 2 po 2 red phosphorous does not react with caustic soda.

Uses of phosphorous : 1. White phosphorous is used in rat poison. 2.red phosphorous is used in match industry

Difference between white phosphorous and red phosphorous PropertyWhite phosphorous Red phosphorous In carbon disulphide SolubleInsoluble In darkGlowsNo glow Melting point44 o c560 o c

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