Indian 10urnal of Chemistry
Vol. 43A, December 2004, pp. 2549-2554
Volumetric properties of transfer of
D( +)-glucose and sucrose from water to
mixed aqueous solutions at 298,15 K
T S Banipal* & Kultar Singh
Department of Applied Chemistry, Guru Nanak Dev University,
Amritsar 143 005, India
Email: [email protected]
and
P K Banipal
Department ofChemislry, Guru Nanak Dev University,
Amritsar 143005, India
Received 6 May 2004; revised 29 September 2004
Apparent molar volumes (<1>, ) and apparent molar compressibilities (Ks.2.~) of D(+)-glucose and sucrose have been determined
in aqueous solutions of potassium chloride (0.5, 1.0, 2.0 and 4.0
mol kg"\ strontium chloride (0.25, 0.5 and 2.0 mol kg-I), barium
chloride (0.25, 0.5 and 1.0 mol kg-I) and guanidine hydrochloride
(0.25, 0.5 and 2.0 mol kg-I) at 298.15 K from their density and
sound velocity data. Partial molar volumes (V'2) and adiabatic
compressibilities (~S. 2) at infinite dilution have been determined
from the respective apparent molar properties and used to calculate partial molar volumes (V'2.I,) and adiabatic compressibilities
(~S.2.1r) of transfer for saccharides from water to aqueous potassium chloride, strontium chloride, barium chloride and guanidine
hydrochloride solutions. Transfer parameters have been discussed
in terms of solute-cosolute interactions on the basis of a cosphere
overlap hydration model. Interaction coefficients have also been
calculated from transfer parameters.
2b
complexed cation. Recently we have observed
higher transfer volumes for D( -)-ribose than
D(-)-arabinose in the presence of CuCI 2.2H20 and
ZnCh, which indicate specific interactions between
2
-OR groups of ribose and metal ions (Cu +/Zn2+) .
Further, higher values of transfer volumes observed
of
for
saccharides
in
the
presence
CuClz.2R20/ZnClz/CaClz than in the presence of
NaCI suggest that the saccharides form stronger
complexes with divalent cations than with
2b
monovalent cations .
In continuation of our work on polyhydroxy
compounds (saccharides and polyols) in aqueous
2
solutions of various cosolutes , we report herein the
apparent molar volumes (<Pv) and apparent molar
compressibilities (KS,2.$) for D( +)-glucose and sucrose
in water and in aqueous 0.5, l.0, 2.0 and 4 .0 mol ki'
potassium chloride, in aqueous 0 .25, 0.5 and 2.0 mol
kg-I strontium chloride, in aqueous 0.25, 0.5 and 1.0
mol kg-I barium chloride and in aqueous 0 .25, 0.5 and
2.0 mol kg-I guanidine hydrochloride solutions from
density and velocity of sound measurements at
298.15K. Partial molar volumes (V'2,tr) and adiabatic
compressibilities (J('S,2,tr) of transfer at infinite
dilution from water to aqueous KCI, SrClz, BaCh and
GU.RCI solutions have been calculated. Interaction
coefficients have been calculated by using McMillanMayer approach. Transfer parameters and interaction
coefficients have been rationalized in terms of solutecosolute interactions.
IPC Code: Int. CI. 7 GOIN
Saccharide molecules having several hydroxy groups
interact with metal ions to produce a variety of metalsaccharide complexes. These complexes are weak, but
the interactions are specific ' -3 . Complexes of
tranSitIOn metal ions like titanium, vanadium,
chromium and manganese with saccharides formed
through ligand oxygens have also been reported4 .
Further, the flexibility of the saccharide molecules is
of considerable relevance for their interactions with
et
ai.
reported I
the
metal cations 5. Morel
thermodynamic properties, !l.Go, Mr and !l.SO, of
association of D(-)-ribose with Sr2+, Ba2+, La3+ and
Gd 3+ cations and concluded that no relationship exists
between these properties and size/charge of the
Experimental
D(+)-Glucose and sucrose (Glaxo Qualigens),
strontium chloride, guanidine hydrochloride and
barium chloride (CDR), and potassium chloride
(SD Fine Chern Ltd) of AR grade were dried and kept
over anhydrous CaCh in a vacuum desiccator for 72
hours. Doubly distilled, degassed and deionised water
having specific conductance I x lO- 6 ohm-I cm-I was
used for preparation of solutions. Densities of the
solutions were measured with a vibrating-tube digital
densitometer (Model DMA 60/602 Anton Paar,
Austria) as reported earlier2. Temperature bath
(Reto BirkerodlDenmark) was used to control the
temperature (±O.OlK) of water around the
densitometer cell. The working of densitometer was
INDIAN J CHEM. SEC A, DECEMBER 2004
2550
checked by measuring the densities of aqueous
sodium chloride solutions and good agreement was
found with the literature values 6 . The precision and
accuracy of density meter were better than 1x 10,6 and
3xlO,6 gcm,3 respectively. All the measurements of
densities of various solutions were made with
reference to pure water having density of 0.997047
gem,3 at 298.15K.
Speed of sound in the solutions was measured with
the help of multi frequency ultrasound interferometer
(M-82, Mittal Enterprises, India) as reported 2d earlier.
Temperature of water flowing around the measuring
cell was controlled within ± 0.01 K. The values of
velocities are accurate within 0 .5 ms" and the
measured value for water at 298.15 K (1496.4 ms" )
agrees very well with the literature2d value
(1496.69 ms" ). All the solutions were prepared on
weight basis using Mettler balance having an
accuracy of ± 0.01 mg.
Results and discussion
Apparent molar volumes (<Pv) and apparent molar
compressibilities (KS.2.4» of D( + )-glucose and sucrose
were calculated in water and aqueous solutions of
(0.5, 1.0, 2.0 and 4.0 mol kg") KCI, (0.25, 0.5 and 2.0
mol kg" ) SrCh , (0.25 , 0.5 and 1.0 mol kg") BaCh
and (0.25 , 0.5 and 2.0 mol kg") GU.HCI from the
experimentally measured densities and velocities of
sound at 298.15K using Eqs 1 and 2.
<Pv = M/d - [(d-do) 1000/m d dol
K S.2.¢
= M Ksld -
[(K"s d - Ks d,,)/I/lddol
... (1)
... (2)
where M is the molar mass of the saccharide, do and d,
the densities (kg m'\ K's and K s the adiabatic
compressibilities (m S'2 kg") of the solvent and
solution respectively and 111 is the molality (mol kg")
of the solution. The adiabatic compressibilities (Ks)
were calculated from the speed of sound (u) of
solutions using Eq. 3.
,
Ks
= l/u
2
d
... (3)
Plots of <Pv or K S,2,rp vs m show linear dependence for
saccharides over the concentration range studied.
Therefore, values of apparent molar volumes (<p°v =
V'") and apparent molar compressibilities (K"S. 2,¢ =
K "S,2) at infinite dilution have been calculated by the
least squares fitting of the Eqs 4 and 5 to the
corresponding data:
<p°v = V iZ + Svl1l
K"S, 2,¢ = f.~Js, z + SKm
... (4)
.. . (5)
where Sv and SK are the experimental slopes. The V iZ.
K's,2, Sv andl SK values alongwith standard devi ations
are summar:ized in Tables I and 2. The literature values 2b.7,9 of V'2 and K'S ,2 in water fo r studied saccha-,
rides (Tables 1 and 2) show excellent agreement with
the present values.
The partli al molar volumes (V' 2,:r) and adiabatic
compressibilities (K' S,2.lr) of transfer of saccharides
from water to aqueous solutions of co-solutes (KCI,
SrCh, BaCh and GU.HCI) at infinite dilution (Tables
1 and 2) have been estimated as follows:
=
I
V'2.I/KJs, z.tr
V 2/K' S,2 (in aqueous solutions of
co-solutes) -- VI/K'S ,2 (in water).
. .. (6)
The plots of V'2,lr and K ' S,2.tr vs In" (molality of
cosolute, mol kg" ) are given in Figs 1 and 2
respectively. V'2.tr values are positive for studied
saccharides and increase with the concentration of the
cosolutes. The magnitude of V' ], lr for sucrose is
greater than for D( + )-glucose in all the studied
cosolutes . The V'2.tr values are alm0st double in the
presence of KCI and GU.HC) f.)r sucrose than that for
glucose whereas this is not tL~ case in other cosolutes
which indicates that the interactions are cation
specific. It may also be noted that the V' 2.tr values for
glucose and sucrose also get levelled off in the case of
KCI and GU.HCI at higher conce ntrations. K JS,2.tr
values are positive in all the cosolutes and increase
with increase in concentration of the cosolutes
(Fig. 2). Further it can be seen that K 'S,2.tr values
increase sharply up to - 0.25 11ls in SrCIz and - 0.5 I1ls
in the rest of the cosolutes and tend to level off after
these concentrations, which may be the level of
saturation of interactions between saccharides and
J
cosolutes. The values of V 2.tr and /(,-'S,2,lr for glucose
and sucrose are higher in the presence of SrCh and
BaCh than in the presence of KCI and GlI.HC!.
Sangster et al'o. reported V J 2 values (213 .555,
215 .856 x 10,6 m 3 mol") only for sucrose in aqueous
KCI solutions at molalities 0.22634 and 0.47908 mol
kg" at 298.15 K. These are higher than the present
J
values, but the dependence of V 2.tr on the
concentration of cosolute is almost similar to that
observed presently. No literature data for V'2.tr and
KOS, 2.1), are available for D(+)-glucose and sucrose in
the presence of SrCIz/BaCI 2/GlI .HCI for comparison.
NOTES
2551
Table I- Partial molar volumes (V'z) of some saccharides in aqueous solutions of KCI, SrC1 2 , BaCl 2 and Gu .HCI and
their transfer values ( V 'Z.lr) at infinite di lution at 298.15K
l
6
3
6
l
Compo
V'z x 10 , m mor t
V'2/r X 10 , m' mOr
In KCf
D(+)-Glucose
Sucrose
Water
112.12
to.04
( 1.385)
112.0"
to. 1
112.7b
to. 1
1I1.94c
to.03
211.32
tOm
(2.706)
211.59c
to.06
0.5 Ills
112. 19
to.03
(0.8095)
1.0111.,
112.63
to.03
(0.903)
2.0 m,
113.08
to.02
( 1.687)
4.0 Ill.,'
113.59
t 0.03
(0.847)
0.5m .•
0.07
1.0llls
0.51
2.0111.,
0.96
4.0111.,.
1.47
212. 17
±0.03
(0.505)
2 12.76
to.03
(0.350)
213.31
t 0.22
( 1.243)
2 14.50
to.13
(0.723)
0.85
1.44
1.99
3.18
0.25 m,
114.01
to.06
(0.948)
211.32
to.05
( 1.720)
0.5 m,
114.39
to.07
(1.133)
213 .30
to. IO
(0.394)
2.0m,
117.40
to. 12
(2.170)
214.40
to.06
(0.954)
0.25 ms
114.22
t 0.08
(1 .299)
214.06
t o. 13
( 1.584)
0.5 ms
115.66
to.08
(0.741 )
214.91
to.04
(1.311)
1.0 m,
116. 18
t 0.03
(0.508)
215 .95
to.05
(0.818)
In SrCfz
D( + )-G Iucose
Sucrose
0.25 m,
1.89
0.5 m,
2.27
2.0 m,
5.38
1.98
3.08
5.66
0.25 m,
2. 15
0.5 ms
3.54
1.0 ms
4.06
2.74
3.59
4.63
0.5 m,
0.51
2.0 ms
0.95
0.88
1.84
In BaCl2
D( + )-G Iucose
Sucrose
III GII.HCI
0.25 m,
0.5 m,
2.0 m,
0.25 ms
D( +)-G Iucose
112.35
112.63
113.08
0.25
±0.01
to.D3
± 0.01
(0.536)
( 1.152)
(0.939)
Sucrose
211.85
212.20
213 . 16
0.53
to.02
t 0.03
to.14
(0.339)
( 1.504)
(0.929)
t Sv values in parenthesis, Ills = molality of KCI, SrC1 2 , BaCI 2 , GU.HCI in water. "Ref.7.
l
Morel et al. " have observed positive V'2.tr values for
D( -)-ri bose and D( -)-arabi nose from water to aqueous
CaCh solutions. Recently, Banipal et al. have
2
reported positive V'2.tr values for several mono-, di-,
tri-saccharides and polyo ls from water to aqueous
NaCI, Gu.HCI, CuCi 2 .2H 2 0 and ZnCIz so lutions.
2d
Positive J(lS.2.tr values for sorbitol and mannitol have
also been observed in aqueous sodium chloride
solutions.
The positive V' 2.tr values can be explained by
analyzing the effect of solute and cosolute on the
structure of water as well as interactions between
bRe f.8. cRef. 2b.
them using different models II . Franks et al" . reported
that partial molar volumes at infinite dilution of a
non-electrolyte is a combination of two factors as
given by Eq. 7 .
.. . (7)
where Villi is the intrinsic molar vo lume of the nonhydrated solute and Vs is the volume due to its
interaction with water. Eq . 7 has been modified as
follows:
... (8)
INDIAN J CHEM, SEC A, DECEMBER 2004
2552
Table 2--Partial molar adiabatic compressibilities (K °S.2) of some saccharides in aqueous solutions of KCI, SrC1 2 ,
BaCI 2 and GU.HCI and their transfer values (K'S.2.tr) at infinite dilution at 298.15K
K'S2 x 1015, m3 mor l Pa' i t
In KCl
Compo
D( + )-G Iucose
Sucrose
Water
-17.63
±0.22
(3.808)
- 17.80a
±0.01
-18.75
±0.12
-18.90"
±0.06
K'S2trX 1015 , m3 mor l Pa'i
0.5 tns
-11.91
±0.05
(0.557)
1.0ms
-8.27
±0.01
(0.985)
2.0ms
-3.75
±0.03
( 1.415)
4.0ms
-1.27
±0.41
(0.847)
0.5ms
5.72
1.0m.•
9.36
2.0m.•
13.88
4.0tns
16.36
-12.76
±0.04
(1.814)
-9.70
±0.01
(0.835)
-6.37
±0.01
(2.035)
-3.61
±0.03
(2.992)
5.99
9.05
12.38
15.14
0.25 m,
-5.42
±0.08
( 1.608)
-2.74
±0.18
(0.647)
0.5ms
-0.89
±0.14
(2.161)
-1.15
± 0.16
(1.101)
2.0 ms
7.14
±0.04
(0.975)
7.74
±0.07
(2.478)
0.25 ms
-II. 70
±O.IO
(4.657)
-12.30
±0.11
(5.044)
0.5 ms
-5.38
±0.29
(4.723)
-7.05
±0.09
(6.444)
1.0ms
-2.54
±0.08
(0.827)
-3.24
±0.09
(1.064)
In SrCt2
D( +)-G Iucose
Sucrose
0.25 ms
12.21
0.5 ms
16.74
2.0ms
24.77
16.01
19.90
26.49
0.25 ms
5,93
0.5 ms
12.65
1.0 ms
15.19
6.45
11.70
15.51
0.5 ms
7.60
2.0 ms
13.35
8.25
14.75
III BaCt2
D(+)-Glucose
Sucrose
III Gu.HCt
2.0m,
0.25 ms
0.25 ms
0.5 ms
3.47
D( + )-G Iucose
-14.14
-10.09
-4.28
±0.04
± 0.11
±0.06
(4.501)
(2.239)
( 1.532)
-3.92
4.35
Sucrose
-14.35
-10.40
±0.06
±0.04
±0.05
(0.848)
(3.356)
(1.495)
t SK values in parenthesis, ms = molality of KCI, SrC1 2 , BaCI 2 , GU.HCI
8
in water, "Ref.9
30
5.5
g
5
4.5
":'.25
"
...~20
Q.
"E 3.5
.,
0
5
3
E 15
on -~
>< 10
-:; 2,5
~
2
1.5
p"t
8
e,;
1
0.5
0
5
0
0
2
3
m" mol kg"
"
5
Fig. I-Partial molar volumes of transfer of some saccharides
from wate:r to aqueous solutions of various co-solutes at different
molalities at 298.15 K: D(+)-Glucose -in KCI, 8; in SrC1 2 , 4; in
BaCi 2, 2; in GU.HCI, 7; Sucrose -in KCI, 5; in SrC1 2 , 3; in BaCI 2,
1; in GU.HCI, 6.
0
2
3
m"mol kg-'
Fig. 2--Partial molar adiabatic compressibiJities of transfer of
some saccharides from water to aqueous solutions of various cosolutes at different molalities at 298.15 K: D(+).. Glucose -in KCl,
6; in SrC1 2, 2; in BaCI 2 , 3; in GU.HCI, 7; Sucrose -in KCI, 8; in
SrC1 2, 1; in BaCI 2, 4; in Gu.HCI, 5.
NOTES
where Vvw is the van der Waal's volume, V void is the
l2
associated void or empty volume and Vshriflkage is the
volume of shrinkage. It has been assumed that Vv•w
and V vnid have the same magnitude in water and mixed
aqueous solutions and thus, the positive volume
change accompanying the transfer of saccharides can
be attributed to the decrease in Vshrinkage in aqueous
solutions of cosolutes, i.e., KClISrChlBaCh/Gu.HCI.
Since GU.HCI is a stronger denaturating agent, in
addition to having some of the structural features of
2c
urea (non-electrolyte), also exists in the ionic form .
Due to the stronger interactions between hydroxyl
groups (-OH) of saccharides with ions of electrolytes,
the effect of -OH groups on water structure is
decreased, thus causing decrease in V,hriflkage'
Dehydration of the ions of these electrolytes may also
take place due to their interactions with saccharide
molecules. In other words, more water will be
released as bulk water in the presence of saccharides.
Since bulk water has a higher volume contribution
than structure-broken water, this factor may also
contribute to positive volume changes. Hence positive
\I" 2.lr results from the decreased effect of solute and
cosolute on water structure \Yhich arises due to
solute-cosolute interactions. The higher magnitude of
\l"2.lr observed for sucrose (consisting of glucose and
fructose units) than for D(+)-glucose reflects the
stronger/extensive interactions between sucrose and
co-solutes.
Cosphere overlap model developed by Gurney l3
has been used to rationalize the V'2.lr data. The
properties of water molecules in the hydration
cosphere depend on the nature of solute species.
According to this model, when two solute molecules
approach each other, their hydration cospheres
overlap and some of this cosphere material is
displaced which results in a change in properties such
as volumes, heat capacities, enthalpies, entropies, etc.
The overlap of ions of cosolutes and saccharides
comes into play because of the interactions between
(i) ions of cosolutes (KClISrChlBaCh/Gu.HCI) and
hydrophilic, -OH sites of saccharide molecules and
(ii) ions of cosolutes and hydrophobic parts/groups of
saccharide molecules. The first type of interactions
contributes positively, whereas the second type
contributes negatively to V'2.lr values 13 • Therefore, the
significant positive V'2.lr values obtained for the
studied saccharides over the entire concentration
range of coso lutes indicate that the hydrophilic-ionic
2553
interactions dominate over the hydrophobic-ionic
interactions.
Banipal et aL. 2a,b have reported similar behaviour
for various saccharides in aqueous solutions of NaCI,
CuCh.2H 20 and ZnCh. The positive \l"2.tr have been
attributed to specific interactions between -OH
2
groups of D(-)-ribose and metal cations (Cu 2+/Zn +),
i.e., to the solute-cosolute interactions in addition to
dehydration of solute and cosolute. The positive
/('S.2,lr values for polyols2d in the presence of sodium
chloride exhibit ion-hydrophilic interactions between
polyols and ions of NaCI. Dehydration of alkali-metal
ions (Li+, Na+ and K+) in the presence of sucrose have
been reported l4 by Gregory and McTigue from e.mJ.
measurements. Morel et al. la have attributed positi ve
volume changes for saccharides in the presence of
CaCh solutions (and vice versa) to solute-cosolute
interactions.
The higher magnitude of V '2 ,tr in the case of SrCb
and BaCh suggest that the interactions between
Sr2+/Ba2+ ions and saccharides are stronger as
compared with K+lNa+ ions. These observations are in
line with those reported by Morel et al. Ib, that divalent
cations form stronger complexes in comparison to
monovalent cations. We have also reported 2b higher
V'2,tr values in aqueous CuCh.2H 20
and ZnCh
solutions than in the case of NaC!, which supports the
above statement that saccharides form more stable
complexes with divalent cations. The positive values
of /('S.2,lr indicate that compressibility of solution
increases in the presence of cosolutes (Fig. 2), which
may again be explained in terms of the interactions
between saccharide molecules and the cosolutes and
their effect on water structure. More water is released
as bulk water due to solute-coso lute interactions and
thus, the effect of saccharide and cosolute on the
water structure is decreased. This released bulk water
is more compressible than the water in the hydration
shells of solute and cosolutes. Dehydration of ions
will also contribute positively to /('S,2,1'" SO both V'2.tr
<Jnd K!'S.2, lr values reinforce the fact that the solutecosolute interactions result in decreased effect of
solute and cosolute on the water structure.
Kozak et al. 15 have proposed a theory based on the
McMillan-Mayer theory l6 of solutions which permits
the formal separation of the effects due to interactions
between pairs of solute molecules and those due to
interactions involving three or more molecules.
The approach has further been discussed by
Friedmann and Krishnan l? and Franks et aL. 18 in order
2554
INDIAN J CI-IEM, SEC A, DECEMBER 2004
to include solute-cosolute interactions in the solvation
spheres. According to this treatment a thermodynamic
tran sfer (YJ2.tr) function at infinite dilution can be
expressed as :
where A and S stand for saccharide and cosolute
respectively. YAS, Y ASS and Y/lSSS are pair, triplet and
quartet
intermolecular
interaction
coefficients
respectively
corresponding
to
a
particular
thermodynamic property. This equation has been
fitted into the transfer data to calculate Y AS and Y/ISS
values. YIIS is positive in all cases whereas the
coeffici ent Y/ISS is negative.
The positive values of pair interaction coefficients
suggest that strong interactions exist between the
saccharides and cosolutes (KCIISrCI 2/BaCI 2/Gu.HCI),
which is again in line with the conclusion drawn from
the cosphere overlap model that solute and cosolute
interactions are dominating over the solute-solvent
interactio ns. The larger pair interaction coefficients in
the case of SrCIzIBaCIz indicate stronger solutecosolute interactions as compared to the interactions
in the presence of KCIIGu.HCI. Thus both the
properties suggest that divalent cations interact
strongly than monovalent cations with the
saccharides . The effect of GU.HCI is almost parallel to
that of a I: 1 electrolyte.
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2
3
4
5
6
7
8
9
10
II
12
13
14
15
16
17
18
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