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Irregularities in the Partial Molar Enthalpies of Mixing of Water and Water-Alcohol Mixtures at Constant Temperature.

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Syntltrsis of I-tetralone (2):
The acid chloride obtained from 1.65 g of 4-phenylbutyric
acid and thionyl chloride was treated with 23 g of
freshly prepared [ I ] polyphosphoric acid with exclusion of
moisture, and the whole was stirred at 70°C for 15 min. HCI
was evolved. The mixture was poured into water and extracted with ether. After washing with 1 0 % sodium hydroxide
solution and drying, the ether was removed, leaving 1.38 g
(94.6 %) of 1-tetralone.
Under the same conditions I-indanone is formed from 3phenylpropionyl chloride, but with only 57.3 % yield.
\
Received: September 18th. 1967
[Z 637 IEI
German version: Angew. Chem. 79, 1100 (1967)
[*I Dr.
A. Bhati and N. Kale
Department of Chemistry and Biology,
Regional College of Technology
Byrom Street
Liverpool 3 (England)
1 1 ) S. Dev, J . Indian chem. SOC.32, 262 (1955).
Irregularities in the Partial Molar Enthalpies of
Mixing of Water and Water-Alcohol Mixtures
at Constant Temperature
By G. Korfiim and K . A . Steinerr*]
I n the neighborhood of specific temperatures, irregularities
(called “kinks” in the Anglo-Saxon literature) occur in the
temperature-dependance of numerous properties of water
and aqueous solutions [I]. They are interpreted as indicating
that such systems contain various mixed phases that are
arranged in the manner of clathrates and are transformed
into one another a t specific temperatures. The best known
example of such a liquid structure if the “water hydrate”
( H 2 0 ) 2 , proposed by Pading, in which one molecule is
surrounded by 20 other molecules, after the manner of a
clathrate; as in gas hydrates, these 20 molecules form the
corners of a dodecahedron. The transition temperatures are
considered t o depend o n the nature and concentration of the
material dissolved in the water, whence it is concluded that
the anomalies denote sudden changes in the structure of the
water and have nothing to d o with interactions between water
and the solutes.
Using a very sensitive differential calorimeter [21 we have
measured the intermediate enthalpy of mixing of water with
water-alcohol mixtures at 30 “C, and from the results have
determined the partial molar enthalpies of mixing as a function of the molar fraction of the components. In contrast to
the measurements by other authors the molar fraction was
varied by very small amounts. Surprisingly, we observed
numerous irregularities which exceeded the experimental
-300
0
02
06
04
Xc2n50n
08
Fig. 1. Partial molar enthalpy of mixing A H E 2 0 of water with warerethanol mixtures. o = our measurements at 30°C; < = calculated
from measurements by Bose 141 at 21 OC. Analogous irregularities were
observed at 20 and 40 “C.
error in the measurements by an order of magnitude. Figure 1
shows some of our results. From them there is no doubt that
structured mixed phases occur also in ethanol-water mixtures,
a fact that may be important for the still IittIe understood
structure of liquids.
It is true that participation of dissolved gases ( 0 2 , N2) in
these structures [31 cannot be excluded with certainty, but
such participation is very unlikely at the temperatures
selected for o u r work. Our measurements further show that
the iregularities in the properties of aqueous solutions are
not determined solely by the structure of the water and its
temperature-dependance, since they are observed at almost
constant temperatures (temperature variations o n mixing
amounted to about 0.01 “ C ) .
Received: October loth, 1967
[Z 638 IE]
German version: Angew. Chem. 79, 1105 (1967)
[ * ] Prof. Dr. G. Kortum and Dipl.-Phys. K. A. Steiner
Institut fur Physikalische Chemie der Universitat
Wilhelmstr. 56
74 Tiibingen (Germany)
[I] M . J . Blundumer, M . F. Fox, and M . C . R. Symons, Nature
(London) 214, 163 (1967); C. Saluma and D. A. I. Goring, J.
physic. Chem. 70, 3838 (1966); W. Drost-Hunsen, Ann. N.Y.
Acad. Sci. 125, 471 (1965).
[2] G. Korriim and H . Schreiber, 2. Naturforsch. 20~7,1030
(1965).
[31 Cf. M . Y. Stuckelberg and W. Meinhold, Z . Elektrochem. Ber.
Bunsenges. 58, 40 (1954).
[4] E . Bose, Nachr. Akad. Wiss. Gottingen, math.-physik. KI.
1906, 278, 316; Z.physik. Chem. 58, 585 (1907).
C O N F E R E N C E REPORTS
Preparation and Properties of Inorganic
Halogenoamines
By J . Junder[*l
Inorganic halogenoamines have recently been obtained by
disproportionation of halogens with ammonia at about
-75 “C. That the reddish-brown NI3.NH3 isolated, inter
ulia, actually has the structure corresponding to this formula
and is not, e.g., a 1:l adduct of NHI2 and NHpI follows
from the reaction (studied analytically and by IR spectroscopy) with pyridine or quinoline, in which the ammonia is
replaced by the nitrogenous bases without destruction of the
NI3 component r11. The structure, which was clarified by BurAngew. Chem. internat. Edit.
Vol. 6 (1967) J No. I2
nighuusen and Hurtl[21 by X-ray analysis shows NI4 tetrahedra which are joined together into chains by common
iodine atoms. One iodine atom of each NI4 tetrahedron is
additionally attached t o one ammonia molecule by a chargetransfer bond.
In order t o explain the decomposition of monochloramine
NH2C1 by way of the unstable imene or nitrene NH, monochloramine was treated with phenyl-lithium in dimethyl-2butene at -75 O C . The expected a-elimination took place in
good yield, as shown by the benzene formed, but only 3
of 2,2,3,3-tetramethylaziridine was obtained. During the
reaction a white precipitate was formed, which evolved NZ
and NH3 when warmed. The precipitate is moderately
soluble in ether at -75OC; LiCl separates from the clear
1087
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constantin, water, enthalpies, irregularities, molar, temperature, mixing, mixtures, partial, alcohol
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