The Neptunium (iv)-neptunium (v) Couple in Perchloric Acid. The Partial Molal Heats and Free Energies of Formation of Neptunium Ions

Measurements on the potentials of the neptunium (III)-(IV) and neptunium (V)-(VI) couples in molal perchloric acid have been reported previously. The present communication deals with the potential data on the neptunium (IV)-(V) couple and the calculations of the partial molal heats and free energies of the neptunium ions in this medium.