Molecule of the Week

Phosphorus pentoxide

September 8, 2008

Phosphorus pentoxide (empirical formula P2O5) is known to many laboratory workers as a powerful desiccant. It is manufactured by burning elemental phosphorus in a current of dry air. P2O5 exists in several crystalline and amorphous forms, the most common of which is the crystalline P4O10 shown. In the fertilizer industry, phosphorus concentration is expressed as weight percent P2O5 equivalent.