4HNO3 + P4O10 → 2N2O5 + 4HPO3
or
2HNO3 + P2O5 → N2O5 + 2HPO3
Nitric acid react with phosphorus pentoxide to produce dinitrogen pentoxide and phosphoric acids. Method of production dinitrogen pentoxide. This reaction takes place at a temperature of -10°C.[16]