Phosphorus is a chemical element with an atomic number of 15, which means that the atomic structure includes 15 protons and 15 electrons. For Phosphorus, the chemical symbol is P. Atomic Mass of Phosphorus The atomic mass of phosphorus is 30.973762 u.

Valence : 1: Hydrogen (-1), +1: 2: Helium: 0: 3: Lithium +1: 4: Beryllium +2: 5: Boron-3, +3: 6:.

diphosphorus pentaoxide. Formula: O 5 P 2. Molecular weight: 141.9445. CAS Registry Number: 1314-56-3. Information on this page: Gas phase ion energetics data. References. Notes. Data at other public NIST sites: