Phase equilibility and specific properties of suspensed solves in the Na2WO4–Nа2СО3–Н2О system at 30 °С

The solubility in the Na₂WO₄–Nа₂СО₃–Н₂О system at 30 °C has been studied. It is shown that chemical compounds and solid solutions are not formed in the system, but with increasing content of sodium tungstate in saturated sodium carbonate solution dehydration of sodium carbonate decahydrate with transformation into b-Nа₂СО₃´7Н₂О occurs. The density, dynamic viscosity and specific electrical conductivity of saturated solutions of the system have been determined, and the isotherms, molar volume, kinematic viscosity, ionic strength, equivalent and reduced electrical conductivity, and apparent molar volume of the sum of salts in the solutions have been calculated. A well-defined correlation in the changes of these properties and solubility in the system is noted.

1. Pilloton R.L., Crawley G.E. A phase equilibrium study in the system Na2WO4–Nа2СО3–Н2О //

2. J. Electrochem. Soc. 1960. V. 107, N 7. Р. 122.

3. Karov Z.G., Semenova S.B., Cheuzheva T.N. Heterogeneous equilibrium and properties of saturated solutions in the Na2MoO4–Na2CO3–H2O system at 25 °C. Chemistry and Technology of Molybdenum and Tungsten. Issue 1. Nalchik, 1971. P. 178.

4. Karov Z.G., Kyarov A.A., Shakov Z.M., Zhilova S.B. Phase equilibrium and properties of saturated solutions in the Na2MoO4–Na2CO3–H2O system. Chemistry of Molybdenum and Tungsten. Issue 2. Nalchik, 1983. P. 94.

5. Kyarov A.A., Khochuev I.Yu., Khasanov V.V., Mirzoev R.S., Kambachokova L.V., Guminyuk O.I. Heterogeneous Equilibrium and Properties of Saturated Solutions in the Na2MoO4–Na2CO3–H2O System at 27 °С. Izvestiya Kabardino-Balkarskogo Gosudarstvennogo Universiteta = Proceeding of the Kabardino-Balkarian State University. 2018;8(1):47–51.

6. Kyarov A.A., Khochuev I.Yu., Mirzoev R.S., Balakhov E.S., Andriyanova L.A., Kaziev A.S. Heterogeneous Equilibrium and Properties of Saturated Solutions in the Na2MoO4–Na2CO3–H2O System at 20 °С // Izvestiya Vysshikh Uchebnykh Zavedeniy. Khimiya i Khimicheskaya Technologiya = Chem. Chem. Tech. 2014;57(2):20–24.

7. Karov Z.G., Kyarov A.A. Heterogeneous equilibrium and properties of saturated solutions in the Na2MoO4–Na2CO3–H2O system at 36 °С. Aspirant i Soiskatel = Aspirant and Applicant. 2003;16(3):158–163.

8. Karov Z.G., Kyarov A.A., Shogenova Z.Kh. Solubility Isotherm and Physical and Chemical Properties of Saturated Solutions of the Na2MoO4–Na2CO3–H2O System. Vestnik Kabardino-Balkarskogo Gosudarstvennogo Universiteta = Bulletin of the Kabardino-Balkarian State University. 2003;5:79–85.

9. Khoсhuev I.G., Kyarov A.A., Kharitonova A.Zh. Heterogeneous Equilibria in the System Sodium Carbonate-Sodium Molybdate-Water at 34 °С. Vestnik Kabardino-Balkarskogo Gosudarstvennogo Universiteta = Bulletin of the Kabardino-Balkarian State University. 1997;2:28–30.

10. Karov Z.G., Kyarov A.A., Khochuev I.G., Shogenova Z.Kh. Investigation of Heterogeneous Equilibrium and Properties of Saturated Solutions of the Na2MoO4–Na2CO3–H2O System at 33 °С. Vestnik Kabardino-Balkarskogo Gosudarstvennogo Universiteta = Bulletin g of the Kabardino-Balkarian State University. 1996;1:16-24.

11. Karov Z.G., Kyarov A.A., Urusova Z.Kh., Afauanova R.Z. Solubility isotherm (30 °С) and some properties of saturated solutions in the Na2MoO4–Na2CO3–H2O system. Zhurnal Neorganicheskoi Khimii = Journal of Inorganic Chemistry. 1988;33(11):2923.

12. Karov Z.G., Kyarov A.A., Lepeshkov I.N., Elmesova R.M. Heterogeneous Equilibria and Properties of Saturated Solutions in the Na2MoO4–Na2CO3–H2O System at 100 °С. Zhurnal Neorganicheskoi Khimii = Journal of Inorganic Chemistry. 1987;32(2):467–472.

13. Karov Z.G., Kyarov A.A., Urusova Z.Kh. Phase Equilibria and Properties of Saturated Solutions in the Na2MoO4–NaI–H2O System at 25 °С. Zhurnal Neorganicheskoi Khimii = Journal of Inorganic Chemistry. 1987;32(2):473–479.