J. Chem. Eng. Data 1982, 27, 84-86
84
Acknowledgment Laboratory assistance by Eldret Parrish, a chemistry graduate, and Joan Smith, a senior in chemistry, is appreciated.
Llterature Cited
.
1
L
0.01
1
3.02
u
-
i i
1
0.03
ConCentratfon Of added f l u o r i d *
0.04 I y
0.05
r102)
Flgwe 4. Fluoride dependence of the solubility of TbF, at 25
O C
(radiometric measurement). discussed in ref 70. The value obtained from our measurements is 1831 f 455, which is comparable with the values 1450 and 1950 reported by Moulin et al. (78) and Bilal et al. ( 19),respectively. he percent of total n3+(aq)that is tied up as terbium monofluoride complex ion in aqueous solution was estimated to be 60.8.
(1) Anderson, K. P.;Buiter. E. A.; Wooliey, E. M. J. Phys. Chem. 1071, 75, 93. (2) Stevenson, P. C.; Nervik. W. E. "The Radiochemistry of the Rare Earths, Scandium, Yttrium and Actinium", NAS-NS 3020, publication under Nuclear Science Series; USAEC. Offlce of Technical Services, Department of Commerce: Washington, DC, 1961; p 18. (3) "IUPAC Solubility Data Project Combined, News Letter 1"; Pergamon Press: Oxford, England, Feb 1980. (4) Dadahaeva G.; Ikarami, D. D. Kokl. Akad. Nauk SSR 1076, 19, 31. (5) Ivanov-Emin, B. N.; Zaitseva, V. A. Zh. Neorg. Khlm. 1067, 12, 2247. (6) Gaikin, N. P.;Shlshkov, Y. D.; Khomyabov, V. I. Radiokhimiya 1978, 20, 136. (7) Vasil'ev, V. P.; Kozlovski, E. V. Zh. Neorg. Khim. 1977, 22, 853. (8) Da Dilva, J.; Frawto, J. R.; Manuela, Q. M. Rev. Port. Quim. 1073, 15, 29; Chem. Absfr. 1075, 129929g. (9) Walker, J. 6.; Choppin, G. R. A&. Chem. Ser. 1067, 7 1 , 127. (10) Menon, M. P. J. Radloend. Chem. 1081. 6 3 , 293. (11) Willard, H. H.; Merrit, J. R.; Dean, L. L. "Instrumental Methods of Analysis", 5th ed.; Van Nostrand: New York, 1974; p 741. (12) Speeding, F. H.; Nelson, R. A.; Rard J. A. J. Chem. Eng. Data 1074, 19,379. (13) Taylor, M. D. Chem. Rev. 1062, 62, 503. (14) Batsonova, L. R.; Lukina, L. V. Russ. J. Inorg. Chem. (Engl. Trans/.) 1072, 17, 629. (15) Weaver, J. L.; Purdy, W. G. Anal. Chlm. Acta 1950, 20, 376. (16) Davies, C. W. "Ion Association"; Butterworths: London, 1962. (17) Karapetyants, M. Kh.; Karapetyants, M. L. "Thermodynamics Constants of Inorganic and Organic Compounds" (translated by J. Schmcrah); Hemphery Science Publishers: Ann Arbor, MI, 1970. (18) Moulin, N.; Hussonnoia, M.; Brillard, L.; Guiliaumont, R. J. J. Inorg. Nuc/. Chem. 1075, 37, 2521. (19) Bllai, B. A.; Kob, B. J. Inorg. Nucl. Chem. 1080, 42, 629. Received for review May 22, 1981. Accepted October 16, 1981. Acknowledgement is made to the donors of the Petroleum Research Fund, administered by the American Chemical Society, for support of this research through their grant no. 11218-83.
Refractlve Index of Molten Salt Hydrates. Mixtures of Tetrahydrates of Calcium and Cadmium Nitrates Surender K. Jaln" and Vljai V. Singh Hindu College, Universky of Delhi, Delhi 7 10007, India
+
Refractive indexes of mdten Ca(N03),.3.97H,0 Cd( NO8),~4.22H,0 mixtures have been measured as functions of temperature and compodtlon. Refractive Index-compoMlon isotherms were found to be linear. Mdar polarizations computed through tho use of the Lorenr-Lorentr equatlon a b varied llnearly wHh compodtlon. The expanshrlties calculated from the temperature cwfficlent of the refractlve index were found to be nearly equal to those obtalned by direct measurement. Introduction I n the past few years, a number of reports concerning physicochemical investigations of molten hydrates have appeared in the literature. These include studies of conductance ( 7 4 ) , viscosity ( 7 - 4 ) , density (2-6), acid-base and electrochemical reactions (7, 8),proton magnetlc resonance spectra ( 9 ) ,ultrasonic absorption (70, 77), Cd2+ diffusion coefficient (72), hydration and associatlon equllbria (73),glass transition temperature (74),surface tension (75, 76), and refractive-index 0021-956018211727-0084801.2510
measurements (77, 78). I t has been shown by Moynihan et ai. (79) that, in the binary hydrate melt system containing tetrahydrates of calcium and cadmium nitrates, both of the cations, e.g., Ca2+and Cd2+, are equally hydrated and the system behaves almost ideally, at least above 60 OC. I n order to complete the physicochemical measurements on thii interesting system, we present in thii paper refracthre-indexmeasurements for the binary system containing the tetrahydrates of calcium and cadmium nitrates.
Experlmentai Sectlon Analytlcal-grade tetrahydrates of calcium nitrate (BDH, Indii) and cadmium nitrate (SM, India) were used as such. Gravimetric analysis and comparison of the density data of the two pure, filtered, and matured melts used in the present study with the precise density vs. composition data of Ewing and Mikovsky (20) and Ewlng and Hem (27) established that the actual H20/CaZ+and H20/Cd2+mole ratios were 3.97 f 0.01 and 4.22 f 0.01, respectively, Mixtures of varying compositions were prepared by mixing the requisite amounts of the melts in glass flasks fitted with airtight groundglass joints and filtering while hot through the 0 1982 American Chemical Society
Journal of Chemical and Englnmrlng Data, Vol. 27, No. 1, 1982 85
Table 1. Refractive Index-Temperature Equations and the Expansivities for Binary Mixtures Containing Tetrahydrates o f Calcium and Cadmium Nitrates Cd2+, mol % 0.0 16.6 19.8 29.8 39.4 49.6 59.6 69.7 79.8 89.9 100.0 O1
no. of data points 6 6 6 6 6 6 6 5 5 5 4
n=a-bt
temp range, "C 30-69 20-70 30-71 21-70 21-70 22-7 1 30-70 31-71 3 1-7 1 31-72 32-71
103b 0.211 0.211 0.219 0.224 0.223 0.224 0.232 0.222 0.235 0.242 0.227
a
1.4717 1.4760 1.4786 1.4822 1.4831 1.4854 1.4883 1.4906 1.4939 1.4971 1.4989
104(SE) 0.6 0.3 0.6 0.5 0.7 0.8 0.9 0.4 0.4 0.1 0.1
1 0 4 a ~ ~ 104aGD: P deg-' deg-' 3.98 4.62 3.94 4.57 4.07 4.73 4.13 4.80 4.10 4.77 4.09 4.77 4.21 4.91 4.09 4.67 4.21 4.92 4.31 5.04 4.01 4.70
~ O ~ C U , ~ deg-' +GD 4.73 1.02 4.94 1.08 4.89 1.03 5.06 1.05 5.15 1.08 4.98 1.04 5.08 1.03 5.05 1.08 5.13 1.04 5.16 1.02 5.19 1.10
All values are for 70 "C.
Table 11. Refractive Index, Molar Volume, and Molar Polarization vs. Mole Fraction Isotherms for Binary Mixtures Containing the Tetrahydrates of Calcium and Cadmium Nitrates temp, "C
Cdz+, mole fraction
A
30 50 70
0-1.0 0-1.0 0-1.0
1.4657 1.4618 1.4575
n=A+BX 1 0 2 ~
2.64 2.56 2.52
V, (cm3 mol-') = A ' 103(s~) 0.43 0.68 0.64
+ B'X
PLL (cm3 mol-') = A " t B"X
A'
E'
SE
A"
B"
SE
135.02 136.34 137.69
3.07 3.22 3.36
0.30 0.30 0.32
37.32 37.38 37.45
2.76 2.79 2.82
0.09 0.09 0.09
0
20
sinteredglass fitters (porosity G-3). The filtered melts were then maintained at about 60 OC to mature for a few hours. Refractive indexes were measured on a PZO, Warszawa (Poland), refractometer (Model RL 1) whose prisms were maintainedat the highest temperature (ca. 70 "C) by circulating water from a constant-temperature bath through the prism comparbnents. A drop of the met was placed directly onto the lower prism and the upper prism was immediately clamped into position. The temperature was then lowered, and measurements were made at certain constant temperatures. In some cases the temperature was raised and measurements were made during the heating cycle also. The measured refractive indexes were reproducible to f0.0002 unit. Results and Discumlon Measured refractive indexes (n) for various mixtures of the Ca(N03),.3.97H20 Cd(NO3),e4.22H2O system are presented in Table Iin the form of least-squares-fitted equations of the type n = a - bt('C) (1)
+
where a and b are arbitrary constants characteristic of the composition. The composition dependence of the refractive index of the system at 30, 50, and 70 O C is shown in Figure 1. The refractive index-composition isotherms are found to be linear and can be described satisfactorily by firstdegree polynomials of the type
(2)
n=A+BX
where x is the moie fraction of cd2+in the mixture. he values of the constants A and B for three typical temperatures are presented In Table 11. Molar volumes (V,) obtained from the measured densities were observed to be additive. The V,-composition jsotherms are recorded in Table 11. Molar polarizations have been calculated by using the Lorenz-Lorentz equation P, =
[(n2
- l)/(n2
+ 2)] v,
(3)
The linear P,-composition isotherm (at 70 "C) is shown in Figure 1, and presented in Table I1 (for 30 and 50 OC also), in the form of the equation PLL(cm3 mol-')
= A"
iB"X
(4)
I 60
40
80
100
H O L E *A Cd2*
Flgwo 1. Refractive index at 30,50, and 70 ' C (In order from above) and molar polarization at 70 O C shown as functions of compositlon of the system.
Table 111. Comparison of the Molar Polarization (PLL) Values with Literature Values salt Ca(NO,), .4. lH, 0 Ca(NO,), .4.OH, 0 Ca(N03), .4.05H,O Ca(NO,), .3.97H,O Cd(N03),.4.12H,0 Cd(N03), .4.22H, 0
ref 22 17 3 present work 3 present work
p ~ ~ ( "C) 3 0 38 (25 "C) 37.31 37.33 37.32 39.39 40.08
where A" and 6"are constants characteristic of temperature. Table I11 presents a facile comparison of the present P, values for the pure metts with those available in the literature. Taking advantage of the nearly temperature-Invariant nature of P,, we calculated the expanskities of these melts from the temperature coefficient of the refractive index and the differential forms of the Gladstone-Dale and Lorenz-Lorentz equations, through the expressions (22) C
X
=~ [ 1/ ( n -
l)](dn/dT)
(5)
86
J. Chem. Eng. Data 1982, 27, 86-89
aLL= (6n/[(n2
-
1Xn2
+ 2)])(dn/dT)
(6)
The computed values of am and au are included in Table I. These are found to be smaller than the directly measured values the discrepancy being greater for au than of expanskitiis (a), for am. A similar observation has been made by Rao et ai. (22),while analyzing their results on Ca(N0,),-4.1H20 KN03 mixtures, and also by Jain ( 3 ) . I n this study, the ratio alaGO has a value of 1.06 f 0.04. This value agrees favorably wlth those reported earlier by Rao et ai. (22) and Jain ( 3 ) . Thus, these studies further support the idea that binary mixtures containing the tetrahydrates of calcium and cadmium nitrates form an ideal molten system.
+
Llterature Clted (1) (2) (3) (4) (5)
An@, C. A. J . Electrochem. Soc. 1085, 772, 1224. Angeil, C. A. J . Phys. Chem. 1088, 70. 3988. Jaln, S. K.; Tamamushi, R. Sc/.Pep. IPCR Jpn. 1980, 7 4 , 73. Moynihan, C. T. J . M y s . Chem. 1086, 7 0 , 3399. Braunsteln, J.; Orr, J.; McDonald, W. J . Chem. Eng. Data 1087, 72, 415.
(6) (7) (8) (9) (10) (11) (12)
(13) (14) (15) (16) (17) (18) (19) (20) (21) (22)
Jain, S. K. J. Chem. Eng. Data 1073, 78, 397. Courgnaud, R. P.; Tremillon, B. BuU. Soc. Ch/m. Fr. 1085, 752. Courgnaud, R. P.; Tremillon, B. BuU. Soc. Ch/m. Fr. 1985, 758. Moynihan, C. T.; Fratiello, A. J . Am. Chem. Soc. 1867, 89, 5546. Darbari, G. S.; Petruccl, S. J. Phys. Chem. 1080, 73, 921. Petrucci, S.; Fettipaldl, F. J. Acoust. Soc. Am. 1087, 42, 517. Braunsteln, J.; Orr, L.; Abarez-Funes, A. R.; Braunstein. H. J. Nectfmnal. Chem. 1067, 15, 337. Braunstein, J.; Braunstein, H., paper presented at the 156th National Meeting of the American Chemical Society, Atlantic City. MI, Sept 8-13, 1968. Angell, C. A.; Sare. E. J.; Bressel, R. D. J. Phys. Chem. 1987, 7 1 , 2759. Jain, S. K. J . Phys. Chem. 1078, 8 2 , 1272. Jaln, S. K. J . Chem. Eng. Data 1078, 2 3 , 170. Jain, S. K. J. Chem. Eng. Data 1078, 2 3 , 216. Jain, S. K. J. Chem. Eng. Data 1078, 23, 266. Moynihan, C. T.; Smailey, C. R.; Angell, C. A,; Sare. E. J. J. Phys. Chem. 1080, 73, 2287. Ewing, W. W.; Mlkovsky, R. J. J . Am. Chem. SOC. 1050, 7 2 , 1390. Ewlng, W. W.; Herty, C. H. J . M y s . Chem. 1053, 5 7 , 245. Rao, K. J.; Helphrey. D. 6.; Angell, C. A. Phys. Chem. Glasses 1073, 14. 26
Received for review March 31, 1981. Accepted October 5. 1981.
Excess Volumes of Binary Mixtures of Isomeric Butyl Chlorides, Pivalonitrile, and Methylchloroform with Nonpolar Solvents RenQ Dlguet Universit6 de Nancy I , Laboratoire de Chimie Thkrique (ERA. no. 22), (2.0. 140, 54037 Nancy Cedex, France
Jan Jadiyn Instytut Fizyki Molekukrnej, Polskiej Akademii Nauk, Smoluchowskiego 17/ 19, 60- 179 Poznafi, Poland
Excess volumes Y E of binary mlxtures of n-butyl chloride, sec -butyl chlorlde, teri-butyl chlorlde, plvalonltrlle, and methylchloroform wlth benzene, carbon tetrachlorlde, cyclohexane, and n-hexane at 203.15 K have been computed from the experhental denolty data. Evldence exists to wggesl that the respactlve molecular shapes of the components play a part In the determlnatlon of V E values.
7
0.10
r' E'
$ 0
-
3
I-0.I0 v X
LLi
-0.20
Introductlon Volume changes on mixing are of interest essentially to test theories of solution and to determine practically composition from density measurements ( I ) . I n this paper, we report the volumetric behavior of some polar substances (n-butyl chbride, sec-butyl chloride, tert-butyl chloride, pivalonitrile, methylchloroform) In nonpolar solvents (benzene, carbon tetrachloride, cyclohexane, n-xane) at 293.15 K and atmospheric pressure. These measwements were made as part of a continuing study on the thermodynamic and electrical properties of liquid mixtures (2-8).
0.5 1 0 0 Mol froct BuCl
0 Mol. f r a c t . I h C !
0
Experknental Sectlon Densities were measured with an accuracy of f5 X g ~ m by- the ~ hydrostatical displacement method previously reported ( 9 ) . The temperature was maintained at 293.15 f 0.05 0021-9568/82/1727-0086$01.25/0
05 1 @ Mol f r a c t 13uCI
Flgwe 1. Molar excess volumes of mixtures of butyl chlorides ((1) n-butyl chlorlde, (2) sec-butyl chloride (3), tert-butyl chloride) with nonpolar solvents ((A) benzene,(B) carbon tetrachloride, (C) n-hexane, (D) cyclohexane) at 293.15 K.
0 1982 American Chemical Society
