Apparent molar volumes and apparent molar heat capacities of aqueous KI, HIO3, NaIO3, and KIO3 at temperatures from 278.15 K to 393.15 K and at the pressure 0.35 MPa
Introduction
Potassium salts of many ions are strong electrolytes in aqueous solutions and find many uses in modern chemistry. The salt KIO3 is one of the most versatile analytical reagents, and the thermodynamic properties of KI have been studied in great detail. In this paper, we compare our calculated values of Vϕ and Cp,ϕ to those reported in the literature for aqueous KI and KIO3. Aqueous solutions of HIO3 have not been studied as extensively, and we also report our values for this system and compare them to the literature values.
In this investigation we report values of Vϕ and Cp,ϕ or aqueous KI, HIO3, and KIO3, as well as values of Cp,ϕ for aqueous NaIO3, and their dependencies on temperature T and molality m. We used results from a vibrating tube densimeter to obtain our values of Vϕ and we used results from a twin fixed-cell temperature scanning calorimeter to obtain our values of Cp,ϕ. We report values of Vϕ for aqueous KI at 0.015 ⩽ (m/mol · kg−1) ⩽ 7.5, for aqueous HIO3 at 0.015 ⩽ (m/mol · kg−1) ⩽ 1.0, and for aqueous KIO3 at 0.01 ⩽ (m/mol · kg−1) ⩽ 0.2, all at 278.15 ⩽ (T/K) ⩽ 368.15 and at p = 0.35 MPa. We report experimental values of Cp,ϕ for KI at 0.015 ⩽ (m/mol · kg−1) ⩽ 5.5, for HIO3 at 0.015 ⩽ (m/mol · kg−1) ⩽ 1.0, for NaIO3 at 0.02 ⩽ (m/mol · kg−1) ⩽ 0.15, and for KIO3 at 0.01 ⩽ (m/mol · kg−1) ⩽ 0.2, all at 278.15 ⩽ (T/K) ⩽ 393.15. Values of Cp,ϕ for aqueous NaIO3 and KIO3 are compared and those for aqueous HIO3 and KIO3 are combined with previously reported Cp,ϕ data for aqueous HCl and KCl [1] to calculate values of Ka, ΔrHm, and ΔrCp,m for the deprotonation reaction of aqueous HIO3.
Section snippets
Experimental
We used potassium iodide (KI, molar mass M2 = 166.0028 g · mol−1, Columbus Chemical Industries, Inc., product no. 4370LB, lot 200120707, reported purity ⩾0.999 mass fraction), iodic acid (HIO3, M2 = 175.9107 g · mol−1, Sigma–Aldrich product no. 221929, lot 05907MC, reported purity = 1.015 mass fraction by thiosulfate titration), sodium iodate (NaIO3, M2 = 197.8923 g · mol−1, Fisher Scientific product no. S322-100, lot 955668, reported purity ⩾0.999 mass fraction), and potassium iodate (KIO3, M2 = 214.0012 g · mol−1,
Results and discussion
Values of Vϕ for aqueous KI, HIO3, and KIO3 were calculated using the following equation:where ρw is the density of water [5]. Our experimental values of ρs(m, T), as well as the calculated values of Vϕ(m, T) and their uncertainties are given in TABLE 1, TABLE 2, TABLE 3 for aqueous KI, HIO3, and KIO3, respectively. The estimated uncertainties in TABLE 1, TABLE 2, TABLE 3 were obtained by using standard error propagation methods as described previously [3].
The
References (28)
- et al.
J. Chem. Thermodyn.
(2001) - et al.
J. Chem. Thermodyn.
(1999) - et al.
J. Chem. Thermodyn.
(2004) - et al.
J. Chem. Thermodyn.
(2003) - et al.
J. Chem. Thermodyn.
(1992) - et al.
Thermochim. Acta
(1979) - et al.
J. Chem. Thermodyn.
(1977) - et al.
Can. J. Chem.
(1986) - International Critical Tables, vol. 3, McGraw-Hill, New York, 1928, p. 55, 87,...
- et al.
J. Chem. Soc.
(1994)
J. Solution Chem.
J. Soution Chem.
Zh. Fiz. Khim.
Trans. Faraday Soc.
Cited by (19)
Volumetric properties of aqueous solution of lithium tetraborate from 283.15 to 363.15 K at 101.325 kPa
2018, Journal of Chemical ThermodynamicsCitation Excerpt :The volumetric property of aqueous electrolyte solutions plays a very important role in elucidating the structural interactions occurring in solution. In order to further researching on the structural interactions occurring in solution, some aqueous systems containing chloride, iodide, nitrate, sulfate have been researched, such as LiCl + H2O [6], NaCl + H2O [7], KCl + H2O, RbCl + H2O, CsCl + H2O [8], MgCl2 + H2O, CdCl2 + H2O [9], CaCl2 + H2O [10], SrCl2 + H2O [11], AlCl3 + H2O, NaCl + KCl + H2O [12], CaCl2 + NaCl + H2O, MgCl2 + NaCl + H2O [13], KCl + CaCl2 + H2O [14], KCl + NaCl + H2O [15], KI + H2O, HIO3 + H2O, NaIO3 + H2O, KIO3 + H2O [16], Mg(NO3)2 + H2O, Sr(NO3)2 + H2O, Mn(NO3)2 + H2O [17], RbNO3 + H2O, CsNO3 + H2O, Sr(NO3)2 + H2O, Y(NO3)3 + H2O, Ga(NO3)3 + H2O [18], Li2SO4 + H2O [19], K2SO4 + H2O [20], Na2SO4 + H2O, +Na2SO4 + NaCl + H2O [21], VOSO4 + H2O [22]. The temperature, concentration, and pressure dependences of the density, apparent and partial molar volumes were reported.
Effect of temperature on compressibility properties of 0.1, 0.5 and 1.0 molal solutions of alkali metal halides. Part 1. Aqueous solutions of sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, potassium iodide, rubidium chloride and rubidium iodide in the 278.15 K to 353.15 K temperature range
2017, Journal of Molecular LiquidsCitation Excerpt :They were also expressed as polynomials of temperature, to perform interpolations for desired concentrations. A very accurate specific heat capacities (from 278.15 K to 393.15 K and at 0.35 MPa) coming from the Woolley group [82,86,89–93,95] and viscosities determined by Isono [104,107] (from 288.15 K to 328.15 K) were preferred in calculations. Introducing values of δT = ± 0.05 K, T = 298.15 K, δCP(T;m) = ± 0.01 J·g− 1, CP(T;m) = 4.138 J·g− 1, δα(T;m) = ± 2·10− 6 K− 1 and α(T;m) = 2.67·10− 4 K− 1 into Eq. (17) we have that δΔκ (T;m) = ± 9.0·10− 14 Pa− 1 which gives the error of about 2.0%.
A Pitzer-based characterization of aqueous magnesium chloride, calcium chloride and potassium iodide solution densities to high temperature and pressure
2013, Fluid Phase EquilibriaCitation Excerpt :Almost 90% of the residuals are between ±0.5 cm3 mol−1. Swenson and Woolley's [33] potassium iodide data at low concentration (m < 0.2) contain large standard errors and exhibit large systematic deviations from their model. Therefore, they were excluded from the present model-fitting.