Mendeleev's Periodic Table > P - Phosphorus

P - Phosphorus

The flammable non-metal was discovered in Germany in 1669 by Hennig Brand who precipitated it from urine. Phosphate buffers are used in general chemistry, and phosphoric acid is used for synthesis in organic chemistry.
Phosphorus is commonly misspelled "phosphorous". It is an essential component of living systems and is found in nervous tissue, bones and cell protoplasm. Phosphorus exists in several allotropic forms including white (or yellow), red, and black (or violet). White phosphorus has two modifications. Ordinary phosphorus is a waxy white solid. When pure, it is colourless and transparent. It is insoluble in water, but soluble in carbon disulphide. It catches fire spontaneously in air, burning to P₄O₁₀, often misnamed as phosphorus pentoxide. When exposed to sunlight, or when heated in its own vapour to 250°C, it is converted to the red variety. This form does not ignite spontaneously and it is a little less dangerous than white phosphorus. The red modification is fairly stable and sublimes with a vapour pressure of 1 atmosphere at 417°C.

Atomic number	-	15		Density	g/mL	1	.82
Atomic weight	u	30	.97376	Melting point	K	317	.3
Bonding radius	A	1	.06	Boiling point	K	550
Atomic radius	A	1	.23	Heat of vaporization	kJ/mol	12	.129
Ionization Potential	V	10	.486	Heat of fusion	kJ/mol	0	.657
Electronegativity	-	2	.19	Specific heat	J/gK	0	.77
The oxide is mildly acidic.				Crystal are monoclinic.
Electron config. : [Ne] 3s² 3p³

Isotopes of P (Phosphorus):

MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	026 20 msec EC/EC2p/ECp,18.120 Si-26/Mg-24/Al-25 26.011776	027 260 msec EC/ECp,11.630 Si-27/Al-26 26.999194	028 270.3 msec EC,14.332 MeV Si-28 27.992312	029 4.142 sec EC,4.943 MeV Si-29 28.981801
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	030 2.498 min EC,4.232 MeV Si-30 29.978313	031 100% Stable 30.973761	032 14.262 da B-,1.711 MeV S-32 31.973907	033 25.34 da B-,5.845 MeV S-33 32.971725
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	034 12.43 sec B-,5.374 MeV S-34 33.973635	035 47.3 sec B-,3.989 MeV S-35 34.973314	036 5.6 sec B-,10.413 MeV S-36 35.978259	037 2.31 sec B-,7.900 MeV S-37 36.979613
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	038 0.64 sec B-/B-n,12.390 S-38/S-37 37.984465	039 0.16 sec B-/B-n,10.510 S-39/S-38 38.986419	040 260 msec B-/B-n,14.500 S-40/S-39 39.991046	041 120 msec B-/B-n,13.800 S-41/S-40 40.994846
MASS abundancy Halflife Particle, Energy Decay Product(s) Isotopic Mass	042 110 msec B-/B-n,17.300 S-42/S-41 42.000107	043 33 msec B-/B-n,15.600 S-43/S-42 43.003327