Oxides, Molybdates, Tungstates, and Related Compounds

Oxides, Molybdates, Tungstates, and Related Compounds. The standard heats of formation of the gaseous compounds NaMo03, Na2Mo03, and Na2Mo04 were determined to be —536.0 33.5, —732.2 58.6 and —1076.5 50kJmol, respectively. Revised values for the dissociation energy (607.1 33.5 kJ mol ) and the standard heat of formation (300.4 + 33.5 kJ mol ) for MoO(g) were also obtained. 

Estimations of the mean amplitudes of vibration for metal—oxygen bonds in MO (M = Mo or W) have been reported together with a force constant of 3.7 mdyne forWO . Raman andi.r. vibrational data for Mo 0 and Mo 04  

The X-ray photoelectron spectrum of Na,W03 (x = 0.547) can be explained by assuming the presence of the three oxidation states for tungsten +6, -1-5, and -1-4. Electrochemical reduction of Na2W04-W03 has been studied and a reappraisal of the electrolysis given in which the tungsten species interacts directly with the cathode according to one of the following equations  

The electrochemical behaviour of the bronzes Na,W03 has been investigated in NaO H solution and the oxide layer of WO3 on the surface of the tungsten bronze found to be much less than in acid media.  

Juryska, Phys. Status Solidi B, 1975,72, K161 (Chem. Abs., 1976,84, 51 783). 

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