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P

Phosphorus

Phosphorus is a chemical element with the symbol P and atomic number 15. It has a standard atomic weight of 30.974, sits in period 3 and group 15, and is classified as a reactive nonmetal.

Properties

SymbolP
Atomic number15
Standard atomic weight30.974
CategoryReactive nonmetal
Group15
Period3
Electron configuration[Ne] 3s2 3p3
Outer-shell electrons5

The figure of 30.974 is a standard atomic weight.

Compounds containing phosphorus

22 of the compounds in this reference contain P, listed by the fraction of their mass it makes up.

CompoundFormulaAtoms% by mass
phosphorusP1100.0%
phosphorus pentoxideO5P2243.6%
phosphoric acidH3O4P131.6%
sodium phosphateNaO4P126.3%
potassium phosphateH2KO4P122.8%
calcium phosphateCa3O8P2220.0%
ATPC10H16N5O13P3318.3%
glyphosateC3H8NO5P118.3%
GTPC10H16N5O14P3317.8%
phosphocreatineC4H10N3O5P114.7%
ADPC10H15N5O10P2214.5%
NADPHC21H30N7O17P3312.5%
coenzyme AC21H36N7O16P3S312.1%
acetyl-CoAC23H38N7O17P3S311.5%
malathionC10H19O6PS219.4%
NADHC21H29N7O14P229.3%
AMPC10H14N5O7P18.9%
chlorpyrifosC9H11Cl3NO3PS18.8%
FADC27H33N9O15P227.9%
cardiolipinC81H141O17P224.3%
lecithinC42H80NO8P14.1%
cyanocobalaminC63H88CoN14O14P12.3%

Calculate with phosphorus

Group 15

Atomic weights are the IUPAC 2021 standard values, abridged to the conventional five significant figures. Group, period, category and electron configuration are derived from the atomic number rather than stored, so they cannot drift out of step with it.