Andriy B. Vishnikin, Olena V. Vishnikina, Yuliia V. Miekh, Olena A. Lykholat


The conditional stability constants for various modifications of molybdenum heteropoly anions (HPAs) having Keggin structure were calculated using the results obtained when constructing the molar ratio curves. A comparative study of the stability of the main analytical forms of HPAs, which were used to determine phosphorus(V) and gallium(III), was carried out including oxidized, metal-substituted, reduced and oxidized forms, as well as those obtained in non-ionic surfactant medium. Based on the results of the study, molybdenum HPAs of phosphorus(V) can be arranged in the next row according to the values of conditional stability constant: PMo12O403- (in a non-ionic surfactant medium) (β = (1.6±0.6)·1040) > H4РBi3+2Mo4VMo7VІO406 (β = (5.6±1.6)·1039) > H4РMo4VMo8VІO403- ((β = 4.9±0.4)·1037) > PMo12O403- (β = 1036). The members of the series with n = 2–4 were the most stable in the series of gallium molybdotungsten HPAs. The stability of various forms of molybdenum HPAs of phosphorus(V) is not very different and is determined by the stability of the entire skeleton of Keggin heteropoly anion. When assessing overall stability of reduced forms of HPAs, it is important to consider their kinetic stability.


heteropoly anion; conditional stability constant; phosphorus(V); gallium(III)

Full Text:



Nagul, E.A., McKelvie, I.D., Worsfold, P., Kolev, S.D. (2015). The molybdenum blue reaction for the determination of orthophosphate revisited: Opening the black box. Anal. Chim. Acta, 890, 60–82.

Vishnikin, A.B., Vishnikina, Ye.V., Chmilenko, F.A. (2007). [Study of conditions of formation and composition of complex formed during the reduction of 12-molybdophosphate with ascorbic acid in the presence of Sb(III) and Bi(III) ions]. Issues Chem. Chem. Technol., (6), 11–15 (in Russian).

Vishnikin, A.B., Miekh, Yu.V., Denisenko, T.A., Kozhemiaka, V.G., Vishnikina, V.Yu., Al-Shwaiyat, M.K.E.A., Bazel, Ya.R., Andruch, V. (2018). [Determination of thiamine as a complex with 11-molybdobismutho(III)phosphate in sequential injection lab-at-valve system. Methods Objects Chem. Anal., 13 (2), 51-59 (in Russian).

Zaruba, S., Vishnikin, A.B., Andruch, V. (2015). Application of solidification of floating organic drop microextraction for inorganic anions: Determination of phosphate in water samples. Microchem. J., 122, 10-15.

Tkach, V.I., Karandeeva, N.I., Tsiganok, L.P., Vishnikin, A.B. (2002). [Use of heteropoly complexes of Keggin structure in analysis of organic and inorganic compounds]. Dnipropetrovsk, Ukraine: USCTU (in Ukrainian).

Vishnikin, A.B., Al-Shwaiyat, M.E.A., Bazel, Ya.R., Andruch, V. (2007). Rapid, sensitive and selective spectrophotometric determination of phosphate as an ion associate of 12-molybdophosphate with Astra Phloxine. Microchim. Acta, 159 (3–4), 371–378.

Dubovik, D.B., Tikhomirova, T.I., Ivanov, A.V., Nesterenko, P.N., Shpigun, O. (2003). Determination of silicon, phosphorous, arsenic, and germanium as heteropoly acids. J. Anal. Chem., 58 (9), 802-819.

Pope, M.T. (1983). Heteropoly and Isopoly Oxometalates. New York, USA: Springer.

Fedorov, A.A., Chernyakhovskaya, F.V., Vernidub, A.S., Ananyevskaya, M.P., Zamaraev, V.P. (1974). [Analytical chemistry of phosphorus]. Moscow, USSR: Nauka (in Russian).

Lyhamn, L., Pettersson, L. (1977). Multicomponent poyanions. 20. Comparison investigation of the Raman spectra of heptamolybdates, molybdophosphates and molybdoarsenates in aqueous solutions and at crystals. Chemica Scripta, 12 (4–5), 142–152.

Pettersson, L., Andersson,I., Ohman, L.-O. (1986). Multicomponent polyanions. 39. Speciation in the aqueous H+-MoO42—HPO42- system as deduced from a combined emf 31P NMR study. Inorg. Chem., 25 (26), 4726–4733.

Tsiganok, L.P., Kleynerman T.V. (1974). Study of stability of molybdenum and tungsten gallium heteropoly complexes in aqueous solutions. Zhurnal Neorganicheskoi Khimii, 19 (8), 2239–2243.

Ueda, T., Hojo, M., Shimizu, K. (2001). Determination of phosphorus Based on the Formation of a Reduced Keggin-Type 12-Molybdophosphate Complex in an Aqueous-Organic Solution. Anal. Sci., 17, 1431–1435.

Savvin, S.B., Chernova, R.K., Stykov, S.N. (1991). [Surface-active substances (Analytical reagents)]. Moscow, USSR: Nauka (in Russian).

Kozhevnikov, I. (2002). Catalysis by polyoxometalates. Chichester, Great Britain: J. Wiley&Sons.

Tsiganok, L.P., Vishnikin, A.B. (1996). [Peculiarities of the formation and reduction reactions of heteropoly complexes of III A Group elements of Periodic table]. Dnipropetrovsk, Ukraine: DSU (in Russian).

Vishnikin, A.B., Svinarenko, T.Ye., Sklenářová, H., Solich, P., Bazel, Ya.R., Andruch, V. (2010). 11-Molybdobismuthophosphate – a new reagent for the determination of ascorbic acid in batch and sequential injection systems. Talanta, 80 (5) 1838–1845.

Vishnikin, A.B. (2005). Novel indirect spectrophotometric methods for determination of phosphate and arsenate using polyoxometalates and micellar medium. J. Molec. Liquids, 118,(1-3), 51–55.

Vishnikin, A.B. (2003). [On interaction of 12-heteropoly anions with non-ionic polyoxyethylated surfactants]. Bull. Dnipropetrovsk Univ. Ser. Chem., 7, 63–67.

Kircher, C.C., Crouch, S.R. (1982). Determination of formation constants of molybdophosphate in strong acid solutions. Anal. Chem., 54 (6), 879–884.

Kiso, Y., Kuzawa, K., Saito, Y., Yamada, T., Nagai, M., Jung, Y.-J., Min, K.-S. (2002). A spot test for aqueous phosphate by color band formation. Anal. Bioanal. Chem., 374, 1212–1217.

Massart, R. (1969). Premiers stades de reduction de l’acide a-silicomolybdique. Ann. Chim., 4, 275–286.

Vishnikin, A.B., Koltsova, E.G., Tsiganok, L.P. (1999). [Investigation of extraction of molybdotungsten heteropoly complexes of gallium]. Zhurnal Neorganicheskoi khimii, 44 (7), 1210–1214.

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Journal of Chemistry and Technologies
eISSN: 2663-2942 | pISSN: 2663-2934
Address of
The journal publishes scientific works on conditions: Creative Commons Attribution 4.0 International License
Founder: Oles Honchar Dnipro National University