Indian Journal of Pure & Applied Physics
Vol. 43, November 2005, pp. 844-848
Ultrasonic velocity of binary mixtures of acetone and dioxane with
dimethylsulphoxide as one component
V K Syal, S Chauhan & Uma Kumari
Chemistry Department, Himachal Pradesh University, Shimla 171 005
Received 20 September 2004; revised 13 April 2005; accepted 16 August 2005
Ultrasonic velocities, densities and viscosities of pure dimethylsulphoxide (DMSO), acetone (Ac) and DMSO + Ac
mixture have been measured for different compositions at 25, 35 and 45°C at 1 MHz and for DMSO + dioxane solvent
systems at 25°C at 2 MHz.Various excess functions e.g. excess adiabatic compressibility (βE), excess volume (VE), excess
viscosity (ηE) etc. have also been evaluated from the measured data and discussed to substantiate the existence of
intermolecular interactions present in liquid mixtures for both the solvent systems.
Keywords: Ultrasonic velocity, Acetone, Dioxane, Dimethylsulphoxide, Viscosiy
IPC Code: B01J19/16
1 Introduction
Dimethylsulphoxide (DMSO) has been recognized
as a good non-aqueous solvent because of its utility in
various chemical and biological reactions1, and in
polymer processing2. Both DMSO and acetone (Ac)
are known to be dipolar aprotic solvents3,4, which
have tendencies to associate through dipole-dipole
interactions. DMSO possesses almost same molecular
volume as that of Ac (DMSO=118.41, Ac=118.45),
but dioxane has higher molar volume (141.9).
Dioxane is known as inert solvent having very low
dielectric constant 2.2 as compared to DMSO (46.6)
and Ac (20.7). Thus the solvents Ac and dioxane
would yield different information when mixed with
DMSO with regard to interactions and solution
structure.
In the present paper, ultrasonic velocities, densities
and viscosities of pure DMSO, Ac and DMSO + Ac
mixture at 1 MHz at 25, 35 and 45°C and for DMSO
+ dioxane solvent systems at 25°C at 2 MHz have
been reported.
2 Experimental Details
The solvents have been purified by the methods as
reported in literature5,6. A detailed procedure for the
measurements of velocity, density and viscosity is
described elsewhere7,8. The values of measured
velocities, densities and viscosities of DMSO, Ac and
dioxane i.e (UDMSO =1487.0 m/s (2 MHz at 25°C),
dDMSO=1.0955 g cm−3, ηDMSO=1.989 cp), (UAc = 1165.0
m/s (1 MHz 25°C), dAc=0.7861 g cm−3, ηAc= 0.304
cp) and (Udioxane=1360.0 m/s (2 MHz 25°C), ddioxane=
1.0296 g cm−3, ηdioxane=1.1960 cp) have been found to
be in good agreement with the literature values5,7,9,10.
The accuracy of density, ultrasonic velocity and
viscosity measurements was determined to be ± 0.02,
± 0.2 and ± 0.2 % respectively.
3 Results and Discussion
The experimentally measured velocity, density and
viscosity values for DMSO, Ac and various DMSO +
Ac mixtures have been reported in Table 1 at 25, 35
and 45°C. For DMSO + dioxane mixtures, the
experimentally measured values of ultrasonic
velocity, density and viscosity at 25°C have been
taken from our previous work6 (Table 2) to calculate
excess parameters.
Any type of positive or negative deviations in these
functions from rectilinear dependence in the above
said functions on composition of the mixture depends
upon specificity of the interactions, their nature and
relative magnitudes between the like and unlike
molecules in the mixtures, which is reflected in terms
of several physical and/or chemical contributions11,12.
Besides, dispersion forces and dipole-dipole
interactions which lead to positive values of excess
functions, another physical contribution, is the
geometrical effect leading to negative ΔKs, LfE and VE
values of functions13. Chemical contribution includes
breaking up of the associates present in pure liquid
(s), resulting in positive ΔKs, LfE and VE, but specific
interactions such as the formation of (new) hydrogen
SYAL et al: ULTRASONIC VELOCITY MEASUREMENTS OF BINARY MIXTURES
845
Table 1—Ultrasonic velocity U (m sec−1), density ρ × 10−3 (kg m−3) and viscosity η × 103 (N m−2 s) in DMSO, Ac and DMSO + Ac
solvent systems at different temperatures at 1 MHz and for DMSO + dioxane system at 25°C at 2 MHz
Mole fraction
of DMSO
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
u
25°C
ρ
η
1165.0
1197.0
1230.4
1263.0
1295.2
1328.0
1360.0
1393.0
1424.6
1458.0
1483.0
0.7861
0.817
0.8488
0.8801
0.9115
0.9426
0.9735
1.0035
1.0340
1.0641
1.0955
0.3040
0.3522
0.4325
0.5055
0.5972
0.7010
0.8520
1.0513
1.3020
1.5820
1.9890
u
Temperature
35°C
ρ
η
U
45°C
ρ
η
1125.0
1161.0
1192.0
1226.0
1258.0
1291.8
1324.0
1358.0
1390.0
1423.0
1456.0
0.7740
0.8057
0.8375
0.8690
0.9004
0.9315
0.9625
0.9930
1.0237
1.0542
1.0854
0.2770
0.3280
0.3782
0.4617
0.5387
0.6404
0.7536
0.9168
1.1109
1.3298
1.6552
1082.0
1120.0
1154.0
1187.0
1223.0
1255.0
1286.0
1320.0
1356.0
1388.0
1422.0
0.7618
0.7939
0.8257
0.8576
0.8890
0.9205
0.9518
0.9825
1.0132
1.0440
1.0755
0.2510
0.2950
0.3586
0.4101
0.4920
0.5925
0.7002
0.8351
0.9920
1.1700
1.3940
Table 2—Ultrasonic velocity U (m sec−1), density ρ (kg m−3) and
viscosity η (N m−2 s) in DMSO, dioxane and DMSO + dioxane
solvent systems at 25°C at 2 MHz
Table 3—Excess function βE (atm−1), LfE (m), VE (m3 mol–1), ηE
(N m−2 s) and specific acoustic impedance ZE (kg m−2 s−1) for
various DMSO + Ac solvent systems at 25°C
XDMSO
U
ρ × 10−3
η × 103
XDMSO
βE × 106
LfE × 1012
VE × 107
ηE × 103
ZE × 10−3
0.00
0.15
0.30
0.45
0.60
0.75
0.90
1.00
1360.0
1376.0
1390.0
1408.0
1429.5
1454.0
1472.5
1487.0
1.0296
1.0377
1.0482
1.0559
1.0668
1.0727
1.0868
1.0955
1.1960
1.2270
1.2850
1.3750
1.5160
1.6670
1.8470
1.9890
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
—
−3.12
−5.53
−6.92
−7.54
−7.55
−6.95
−5.89
−4.35
−0.64
—
—
−0.75
−1.38
−1.75
−1.94
−1.98
−1.86
−1.61
−1.22
−0.76
—
—
−0.8439
−2.2134
−2.8847
−3.4120
−3.4262
−3.2751
−2.2597
−1.4995
−0.3666
—
—
−0.1203
−0.2085
−0.3040
−0.3808
−0.4455
−0.4630
−0.4322
−0.3500
−0.2385
—
—
−8.74
−13.21
−16.89
−18.76
−18.59
−17.15
−17.11
−09.83
−2.29
—
bonds, charge transfer complexes and other type of
complex forming interactions between component
molecules result in negative ΔKs, LfE and VE values.
The excess functions for isentropic compressibility,
β, volume, V, viscosity, η, intermolecular free length,
Lf and acoustic impedance Z have been evaluated
using the following relation14.
YE = Yexp−[Y1(1−x1) + Y2x2]
…(2)
where Y represents the respective intensive physicochemical quantity, namely, βexp and ηexp , which
represent compressibility and viscosity of mixtures,
and βi and ηi refer to the compressibility and viscosity
of pure components i and xi being their mole fractions
in the mixture (Tables 1 and 2). The excess
parameters have been reported in Tables 3 and 4.
The dependence of excess function on the mole
fraction, x, have been fitted to the Redlich-Kister15
equation given below by the least square method:
n
YE = X1 X2 ∑ Ai (1−2xi) i−1
…(3)
i=0
YE represents the respective physico-chemical
property of the binary solvent system. The values of
coefficients, A1, A2, A3, A4 and A5, of Eq. (3), along
with their standard deviations are reported in Tables 3
and 4. The standard deviations σ(YE) have been
calculated as:
1
⎡ Σ(YobE − YcalE ) 2 ⎤ 2
σ (YE) = ⎢
⎥
n− p
⎣
⎦
…(4)
where n is the total number of data points and p is the
total number of coefficients Ai [(p=5) in the present
case] which have been used in Eq. (4).
INDIAN J PURE & APPL PHYS, VOL 43, NOVEMBER 2005
846
Table 4—Excess function βE (atm−1), LfE (m), VE (m3 mol–1), ηE
(N m−2 s) and specific acoustic impedance ZE (kg m−2 s−1) for
various DMSO + Ac solvent systems at 35°C
XDMSO
0.00
βE × 106
—
LfE × 1012
—
VE × 107
—
ηE × 103
—
ZE × 10−3
—
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
−4.19
−6.40
−8.04
−8.56
−8.55
−7.74
−6.52
−4.68
−2.57
—
−1.0
−1.55
−1.99
−2.13
−2.17
−1.97
−1.69
−1.22
−0.69
—
−1.587
−2.911
−3.658
−4.056
−3.986
−3.646
−2.771
−1.906
−0.775
—
−0.0868
−0.1744
−0.2288
−0.2896
−0.3257
−0.3503
−0.3247
−0.2686
−0.1874
—
−6.29
−14.37
−18.23
−21.88
−22.23
−22.16
−18.97
−15.48
−08.20
—
Fig. 1—Plots of excess compressibility βE (atm−1) vs. mole
fraction of DMSO (XDMSO) in DMSO + Ac solvent system at
different temperatures
3.1 DMSO + Ac system
From the plots given in Figures 1-3, it is clear that
with the increase of content of DMSO to Ac, excess
function values of βE, VE and ηE decrease negatively
in magnitude and approach minimum at around 50
mole % of DMSO which suggest that maximum
structural changes take place in this region of the
solvent mixtures. In DMSO + MeOH and DMF +
MeOH solvent system14, a broad minimum for βE was
observed at around 60-80 mole % MeOH and as these
two systems are characterized by strong hydrogen
bond interactions, the results were interpreted in terms
of strong structural consequences of intermolecular
interactions. Such structural consequences due to
hydrogen bond intermolecular interactions are not
reflected by the excess function values in DMSO +
Ac systems, being non-hydrogen bonded solvents.
However, similar observations have also been
reported for ethyl methyl ketone (EMK) and N,Ndimethylformamide9 (DMF) and acetonitrile (AN) +
propylene carbonate10,16 (PC) mixtures by Syal and
co-workers9. Further, in literature, relatively large
negative values of βE and ηE for non-hydrogen bonded
systems like AN-DMSO, butyronitrile-Ac17, BN-AN13
mixtures have been attributed to dipole-dipole
interactions. However, in binary mixtures of diisobutyl ketone (DIBK) with chlorobenzene and
bromobenzene and toluene, a negative βE has been
reported in bromo and chlorobenzene but is found to
be positive in toluene18. Increasing negative βE and VE
values with increase of temperature in DMSO + Ac
mixtures as shown in (Figs 1 and 2) may be accounted
for the fact that the disruption of molecular
association in Ac molecules leads to closer packing in
Fig. 2—Plots of excess volume VE (m3 mole−1) versus mole
fraction of DMSO (X DMSO) in DMSO + Ac solvent system at
different temperatures
Fig.3—Plots of excess viscosity ηE (N m−2 s) versus mole fraction
of DMSO (X DMSO) in DMSO + Ac solvent system at different
temperatures
SYAL et al: ULTRASONIC VELOCITY MEASUREMENTS OF BINARY MIXTURES
DMSO + Ac mixtures and hence reduction in
compressibility and volume. However, it may be
noted from the Figs (1-3) that there is an interesting
contrast between the mode of variation of ηE to those
of βE and VE values with temperature. The term ηE
tends to become less negative whereas βE and VE
become more negative with rise in temperature.
Similar observations have been reported in DMSO +
PC, DMSO + MeOH mixtures14. Less negative ηE
effect in DMSO + Ac can be attributed to the thermal
effect due to increase of temperature by which
association between DMSO and Ac molecules
themselves is decreased, but intermolecular
association between DMSO and Ac molecules is
increased, and hence excess viscosity is increased
with the increase of temperature. This is further
supported by the fact that VE decreases with the
increase of temperature. Negative deviation in
viscosity is generally attributed to the weakening of
the association between the component molecules,
which results in greater fluidity of the molecule i.e. to
say a decrease in viscosity of mixture with regard to
ideal mixture. However, with increase in temperature,
ηE values tend to be more positive which is in
agreement with ηE values for DMSO + MeOH and
DMSO + DMF systems14. Retzolins et al.19 have also
reported that negative ηE values for AN-toluene
mixtures decrease with rise in temperature. A
correlation between the sign of ηE and VE values for a
number of binary solvents system was reported by
Prolongo et al.20 and by Dewan et al.21 suggesting
dispersion and dipolar interactions rather than
hydrogen bond formation makes ηE more negative.
As a result, the negative ηE values for DMSO + Ac
solvent system, therefore, can be attributed primarily
due to dipole-dipole type of interactions between
DMSO and Ac molecules.
847
Fig. 4—Plot of excess free length LfE (m) versus mole fraction of
DMSO (XDMSO) in DMSO + dioxane solvent system at 25°C
Fig. 5—Plot of excess viscosity ηE (N m−2 s) versus mole fraction
of DMSO (XDMSO) in DMSO + dioxane solvent system at 25°C
3.2 DMSO + Dioxane
For DMSO + dioxane mixtures, excess function βE
and LfE (Fig. 4) values show positive deviation i.e.
increase positively in magnitude, showing a
maximum at 45 mole % of DMSO. However, for ηE
and ZE, (Figs 5 and 6) the values are found to be
negative over the entire solvent composition range,
decrease in magnitude reaching minimum at 45 mole
% DMSO and then increase with increase in DMSO
content in the solvent mixture. In THF + alkanol
system22, the observed positive βE and VE values over
whole composition range have been attributed to the
fact that rupturing of hydrogen bonded associates of
Fig. 6 —Plot of excess specific acoustic impedance ZE (kg m−2
s−1) versus mole fraction of DMSO (XDMSO) in DMSO + dioxane
solvent system at 25°C
INDIAN J PURE & APPL PHYS, VOL 43, NOVEMBER 2005
848
Table 5—Excess function βE (atm−1), LfE (m), VE (m3 mol–1), ηE
(N m−2 s) and specific acoustic impedance ZE (kg m−2 s−1) for
various DMSO + Ac solvent systems at 45°C
XDMSO
βE × 106
LfE × 1012
VE × 107
ηE × 103
ZE × 10−3
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
—
−5.16
−8.06
−9.65
−10.60
−10.21
−9.03
−7.51
−5.61
−2.91
—
—
−1.26
−1.96
−2.35
−2.65
−2.56
−2.25
−1.89
−1.46
−0.74
—
—
−1.981
−3.255
−4.253
−4.503
−4.570
−4.240
−3.253
−2.107
−0.885
—
—
−0.0703
−0.1210
−0.1838
−0.2162
−0.2300
−0.2360
−0.2160
−0.1734
−0.1097
—
—
−05.60
−12.43
−17.82
−19.06
−21.59
−23.31
−20.93
−14.44
−09.78
—
alkanols dominate over hydrogen bonding between
unlike molecules. The ηE behaviour (negative in
magnitude) is similar to that observed for DMSO +
Ac systems. Positive βE, however, can be attributed to
the formation of association between DMSO (dipolar
aprotic solvent molecule) and dioxane (inert solvent
molecule), since dioxane has dielectric constant value
≈ 2.0 at 25°C, which is far less than 46.4 for DMSO
(Table 5). Also, there is large difference in size of
molecules (molar volume for DMSO = 118.4 and
dioxane = 141.9) leading to closer packing of DMSO
molecules into dioxane molecules. Mixing of dioxane
to DMSO or vice versa will lower the dielectric
constant of the mixture, there by increasing
Coulombic forces of attraction. In MeOH +CCl4
mixtures23 also, positive βE has been reported which is
attributed to the formation of species not too large to
undergo close packing as BN -MeOH or AN-MeOH
mixture.
Thus, it can be concluded that in DMSO + Ac
mixture, dipole-dipole interaction/repulsion forces
may have predominant effect than association
whereas in DMSO + dioxane mixture, association
between DMSO and dioxane molecules may have
important role to play.
Acknowledgement
V K Syal and S Chauhan thank University Grants
Commission (UGC), New Delhi, for sanction of
Project No.F 12-145/2001/(SR-1) and Uma Kumari
thanks Director of Education, Himachal Pradesh for
sanctioning study leave for completion of this work to
complete the research.
References
1 Pal A & Kumar H, J Mol Liq, 94 (2001) 163.
2 Mehra R & Israni R, Indian J Chem Tech, 9 (2001) 341.
3 Kinginger J B, Tannahill M M, Greenberg M S & Popov A J,
J Phys Chem, 77 (1973) 2444.
4 Hill N E & W E Vanghan, Dielectric properties & molecular
behaviour (Van Nostr & Reinhold, New York), P-31 (1969)
5 Syal V K, Chauhan S & Chauhan M S, Z Phys Chem (NF),
49 (1988) 159.
6 Syal V K, Kumari Uma, Chauhan S & Chauhan M S, Indian
J Pure & Appl Phys, 30 (1992) 719.
7 Syal V K, Chauhan S, Katoch A & Chauhan M S, Czech
Chem Commun, 56 (1991) 1803.
8 Syal V K, Chauhan S & Goutam R, Ultrasonics, 36 (1998)
623.
9 Syal V K, Patial B S & Chauhan S, Indian J Pure & Appl
Phys, 37 (1999) 366.
10 Chauhan S, Syal V K & Chauhan M S, Indian J Pure & Appl
Phys, 32 (1994) 186.
11 Marcus Y, Introduction to liquid state chemistry (Wiley
Interscience, NY) (1977).
12 Assarson P & Erich F R, J Phys Chem, 72 (1968) 2710.
13 Fort R J & Moore W R, Trans Faraday Soc, 61 (1965) 1112.
14 Chauhan M S, Sharma K C, Gupta S, Sharma M & Chauhan
S, Acoust Lett, 18 (1995) 233.
15 Redlich O & Kister A T, Indian Engg Chem, 40 (1948) 345.
16 Chauhan S, Syal V K & Chauhan M S, Indian J Pure &
Appl Phys, 33 (1995) 92.
17 Gill D S & Harkiran Tranjit K, J Chem Soc, 89 (1993) 1737.
18 Acharya S, Paikray R & Mohanty G C, Indian J Pure & Appl
Phys, 41 (2003) 855.
19 Retzolins G, Popadopoulos N & Jaunnakoudkis D, J Chem
Engg Data, 31 (1986) 146.
20 Prolongo M G, Maregosa R M & Fuentes I H, J Phys Chem,
88 (1984) 2163.
21 Dewan R K, Gupta S P & Mehta S K, J Soln Chem, 18
(1989) 13.
22 Ali A, Nain A K, Sharma V K & Ahmed S, Indian J Pure &
Appl Phys, 42 (2004) 663.
23 Parmanik R & Bagehi S, J Ind Chem Soc, 80 (2003) 335.