Molybdophosphoric acid

H3[PMoi204o] I2H2O is a yellow crystalline solid a yellow-green color indicates the presence of lower-valent Mo or Mo impurities. The compound is highly soluble in water, ethanol, ether, and acetone, but is insoluble in 

Characterize your sample by one or more of the following techniques elemental analysis (P and/or Mo), UV-vis spectroscopy (2x 10 M in 0.1 M HCl), FTIR (KBr pellet or Nujol muU), or thermogravimetric analysis to determine the number of waters of hydration (heat the sample 10°Cmin from room temperature to 700°C under air or nitrogen atmosphere). 

For each experiment you did, what was your percentage yield, based on the limiting reagent Explain the possible reasons for any disagreement between your yield and the expected yield. 

Based on the FTIR spectra, discuss the strength of the bonds in the Keggin structure. 

Compare the obtained powder XRD profile with the standard ICDD (International Centre for Diffraetion Data) file for this eompound. 

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A final requirement for a chemical kinetic method of analysis is that it must be possible to monitor the reaction s progress by following the change in concentration for one of the reactants or products as a function of time. Which species is used is not important thus, in a quantitative analysis the rate can be measured by monitoring the analyte, a reagent reacting with the analyte, or a product. For example, the concentration of phosphate can be determined by monitoring its reaction with Mo(VI) to form 12-molybdophosphoric acid (12-MPA). 

An iron phosphate catalyst with a P/Fe atomic ratio of 1.2 used in this study was prepared according to the procedures described in the previous studies [6-8]. On the other hand, a V-P oxide catalyst with a P/V atomic ratio of 1.06 and pumice supported 12-molybdophosphoric acid (H3PM012O40) and its cesium salt (CS2HPM012O40) catalysts were the same as used in a previous study [9]. Pumice supported W03-based mixed oxide catalysts were the same as used in a previous study [10]. 

In organic solvents Many of the free acids and a few of the salts are very soluble in organic solvents, especially if the latter contain oxygen. Ethers, alcohols, and ketones (in that order) are generally the best solvents. The dehydrated salts sometimes dissolve readily in organic solvents the hydrated salts are insoluble. Both 12-molybdophosphoric acid and its cobalt salt can be dissolved and recovered intact from molten benzoic acid solutions5. ... 

Recent determinations of molecular weight by ultracentrifugation possibly indicate a monomeric 11-molybdophosphate as the principal species formed by dissolving 12-molybdophosphoric acid in a buffer of pH 4.52 . Other evidence more strongly supports the existence of 11-molybdophosphates in solution2 . Solid 11-molybdo-phosphates have also been reported. The 11-complexes appear to differ in properties from the 12-anions. For example, they are said to be relatively inert to reduction12 . 

Ammonium salts of both acids are readily soluble. This property may be used to remove traces of 12-molybdophosphoric acid from 9-molybdophosphoric acid. However, salts of pyridine, alkaloids, and some other organic bases are insoluble. 

Heravi, M.M., Bakhtiari, K., and Bamoharram, F.F. 2006a. 12-Molybdophosphoric acid A recyclable catalyst for the synthesis of Biginelli-type 3,4-dihydropyrimidine-2(lH)-ones. Catalysis Communications, 7 373-76. 

More recently, heteropolyacids like 12-molybdophosphoric acid (H3PM012O40) have been found to be the very efficient initiators of cationic ring-opening polymerization [13]. They are easily available, inexpensive initiators with an acid strength comparable to perchloric acid they are easily purified and conveniently handled in a pure state [14]. 

It is interesting to note that reduced heteropoly compounds show higher selectivity towards methacrylic acid than the non-reduced ones in the oxidation of isobutane. Mizuno and coworkers have also reported the oxidation of isobutane under oxygen-deficient conditions [67]. Ueda and coworkers have studied reduced 12-molybdophosphoric acid for the oxidation of propane [79]. This highly reduced... 

The sodium salt described above has been show to be an acid salt of composition Na3H4[P(Mog07)6]19H20. The heptabasic silver and mercurous salts formed by precipitation from solutions of 12-molybdophosphoric acid by means of the metal nitrates are very probably the normal salts of the acid. 

Instead of chemical oxidative polymerization, electropolymerization can also be considered. A recent study shows that slow but efficient electropolymerization is possible if anilinium-exchanged zeolite Y is subjected to oxidative treatment at the electrode-electrolyte interface. Cyclic voltammetric signatures of the polymerization suggest that it occurs mostly through one dimer (p-aminodiphenylamine) which imdergoes oxidative polymerization. Electrochemical polymerization of aniline in zeolite molecular sieves was studied. A zeolite-modified electrode showed shape-selectivity for 12-molybdophosphoric acid. 

Fundamental correlations between redox properties and catalytic activity have successfully been established for the hydrogen form and alkali salts of 12-molybdophosphoric acid [1]. Provided that the contributions of surface- and bulk-type catalysis are properly taken into account, good monotonic relationships are obtained between the catalytic activity for oxidation and the reducibihty (or the oxidizing power) of the catalyst. The rate of oxidation of aldehydes, a surface-type reaction, correlates linearly with the surface reducibility of the catalyst, and the rate of oxidative dehydrogenation of cyclohexene, a bulk-type reaction, with the bulk reducibility [2]. 

Ueda et al. applied reduced 12-molybdophosphoric acid to the oxidation of propane and obtained 50% selectivity to acrylic acid and acrolein at 12% conversion [22, 23]. 

The oxidation of methane has also been studied with heteropoly oxometalates as heterogeneous catalysts (ref. 17). While a number of these solids was examined the highest activity and selectivity were found with 12-molybdophosphoric acid supported on silica with N O as oxidant. 

Na3[PvMoI204o] Sodium 12-molybdophosphate sodium dodecamolybdophosphate H3[PvMo 204o] 12-Molybdophosphoric acid dodecamolybdophosphoric acid... 

Molybdophosphoric acid dodecamolybdr sphoric acid Dimeric potassium 6-tungstocobaltate dim potassium hexa-tungstocobaltate(n)... 

Mukai and co-workers [105] used Keggin-type heteropolyacids immobilized in the network structure of resorcinol-formaldehyde carbon gels as catalysts for the synthesis of methyl tert-butyl ether from methyl alcohol and tert-butyl alcohol. Large amounts of 12-tungstophosphoric and 12-molybdophosphoric acids were immobilized into the support by two methods, pore shrinkage and the ship-in-the-bottle method, which are essentially impregnation methods. The authors reported that these catalysts showed activity in the reaction studied and could be of practical utility as solid acid catalysts in various reactions. 

Tin(ii) chloride reacts with bis(ferrocenyl- and cymantrenyl-)mercury in co-ordinating solvents such as THF to form bis-(ferrocenyl)- and -(cyman-trenyl)- tin dichloride, respectively. 12-Molybdophosphoric acid is reduced by tin(ii) chloride in four steps, in each of which one equivalent of SnCl2 is consumed, and the heteropoly anion accepts two electrons. ... 

Molybdic acid, sodium salt. See. Sodium molybdate anhydrous Molybdic oxide. See Molybdenum trioxide Molybdic sulfide. See Molybdenum disulfide Molybdic trioxide. See Molybdenum trioxide Molybdophosphoric acid 12-Molybdophosphoric acid. See Phosphomoiybdic acid... 

N. Feng, A. Zheng, S.J. Huang, H. Zhang, N. Yu, C.Y. Yang, S.B. Liu, F. Deng, Combined solid-state NMR and theoretical calculation studies of Bronsted acid properties in anhydrous 12-molybdophosphoric acid, J. Phys. Chem. C 114 (2010) 15464-15472. 

Place sample (unknown or standard phosphate solution. A) in a 5-mL volumetric flask and add 0.500 mL of B and 0.200 mL of C. Dilute to almost 5 mL with water and heat at 100°C for 10 min to form a blue product (H3P04(Mo03)i2, 12-molybdophosphoric acid). Cool the flask to room temperature, dilute to the mark with water, mix well, and measure absorbance at 830 nm in a 1.00-cm cell. 

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