PHOSPHORUS
NITROGEN GROUP
| Atomic number: | 15 |
| Group numbers: | 15 |
| Period: | 3 |
| Electronic configuration: | [Ne] 3s2 3p3 |
| Formal oxidation number: | -3 +3 +5 |
| Electronegativities: | 2.19 |
| Atomic radius / pm: | 110.5 |
| Relative atomic mass: | 30.973 761 998(5) |
Phosphorus was discovered by Hennig Brandt (DE) in 1669. The origin of the name comes from the Greek word phosphoros meaning bringer of light. White phosphorus is white to yellow soft, waxy phosphorescent solid with acrid fumes. It's Toxic by inhalation, ingestion, or skin contact. Red phosphorus is powdery, non-flammable and non-toxic. Phosphorus is most often found in phosphate rock. Pure form is obtained by heating a mixture of phosphate rock, coke and silica to about 1450 °C. It is used in the production of fertilizers and detergents. Some is used in fireworks, safety matches and incendiary weapons. Phosphorus is also important in the production of steels, phosphor bronze and many other products. The price of 99 % pure phosphorus powder is 43.90 € for 500 g.
| Density / g dm-3: | 1820 | (white, 293 K) |
| 2200 | (red, 293 K) | |
| 2690 | (black, 293 K) | |
| Molar volume / cm3mol-1: | 17.02 | (white, 293 K) |
| 14.08 | (red, 293 K) | |
| 11.51 | (black, 293 K) | |
| Electrical resistivity / µΩcm: | 1E+17 | (20 °C) |
| Thermal conductivity / W m-1K-1: | 0.235 |
| Melting point / °C: | 44.15 |
| Boiling point / °C: | 280.5 |
| Heat of fusion / kJ mol-1: | 2.51 |
| Heat of vaporization / kJ mol-1: | 51.9 |
| Heat of atomization / kJ mol-1: | 314 |
| First ionization energy / kJ mol-1: | 1011.82 |
| Second ionization energy / kJ mol-1: | 1907.47 |
| Third ionization energy / kJ mol-1: | 2914.14 |
| in the atmosphere / ppm: | - |
| in the Earth's crust / ppm: | 1050 |
| in the oceans / ppm: | 0.07 |
| Crystal structure: | simple cubic |
| Unit-cell dimensions / pm: | a=1131 |
| Space group: | Pm3m |
| Isotope | Relative atomic mass | Mass percent (%) |
|---|---|---|
| 31P | 30.9737615(2) | 100 |
| Balanced half-reaction | Eo / V | |
|---|---|---|
| PO43- + 3H+ + 2e- → HPO32- + H2O | +0.121 | |
| HPO42- + 2H+ + 2e- → HPO32- + H2O | - 0.234 | |
| H2PO4- + H+ + 2e- → HPO32- + H2O | - 0.447 | |
| H2PO4- + 2H+ + 2e- → H2PO3- + H2O | - 0.260 | |
| H3PO4 + H+ + 2e- → H2PO3- + H2O | - 0.329 | |
| H3PO4 + 2H+ + 2e- → H3PO3 + H2O | - 0.276 | |
| PO43- + 8H+ + 5e- → P (red) + 4H2O | - 0.128 | |
| PO43- + 8H+ + 5e- → P (white) + 4H2O | - 0.156 | |
| HPO42- + 7H+ + 5e- → P (red) + 4H2O | - 0.288 | |
| HPO42- + 7H+ + 5e- → P (white) + 4H2O | - 0.316 | |
| H2PO4- + 6H+ + 5e- → P (red) + 4H2O | - 0.358 | |
| H2PO4- + 6H+ + 5e- → P (white) + 4H2O | - 0.386 | |
| H3PO4 + 5H+ + 5e- → P (red) + 4H2O | - 0.383 | |
| H3PO4 + 5H+ + 5e- → P (white) + 4H2O | - 0.411 | |
| PO43- + 11H+ + 8e- → PH3(g) + 4H2O | - 0.123 | |
| HPO42- + 10H+ + 8e- → PH3(g) + 4H2O | - 0.212 | |
| H2PO4- + 9H+ + 8e- → PH3(g) + 4H2O | - 0.265 | |
| H3PO4 + 8H+ + 8e- → PH3(g) + 4H2O | - 0.281 | |
| H3PO3 + 2H+ + 2e- → H3PO2 + H2O | - 0.499 | |
| HPO32- + 5H+ + 3e- → P (red) + 3H2O | - 0.298 | |
| HPO32- + 5H+ + 3e- → P (white) + 3H2O | - 0.346 | |
| H2PO3- + 4H+ + 3e- → P (red) + 3H2O | - 0.419 | |
| H2PO3- + 4H+ + 3e- → P (white) + 3H2O | - 0.467 | |
| H3PO3 + 3H+ + 3e- → P (red) + 3H2O | - 0.454 | |
| H3PO3 + 3H+ + 3e- → P (white) + 3H2O | - 0.502 | |
| H4P2O6 + 2H+ + 2e- → 2H3PO3 | +0.38 | |
| 2H3PO4 + 2H+ + 2e- → H4P2O6 + 2H2O | - 0.94 | |
| P (red) + 3H+ + 3e- → PH3(g) | - 0.111 | |
| P (white) + 3H+ + 3e- → PH3(g) | - 0.063 |
| 14 Silicon | ← | 15 Phosphorus | → | 16 Sulphur |
Citing this page:
Generalic, Eni. "Phosphorus." EniG. Periodic Table of the Elements. KTF-Split, 18 Jan. 2024. Web. {Date of access}. <https://www.periodni.com/p.html>.
