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Kinetics of the reaction of thiourea with methyl iodide
in aqueous solutions at the temperatures 25°, 35° and 40°C
has been investigated.
The reaction was found to be dimolecular. The rate of
the reaction is not affected by pH of solution with in the
range 4.00 - 9.06. Activation energy of the reactions is
74.07 KJ/mole K.
Enthalpy of solution of NaI in water-isopropanol mixtures with the addition of formamide and of N,N-dimethylformamide
was measured. The course of relation of standard enthalpy of NaI solution in the investigated mixed
solvents vs. alcohol and amide contents was discussed.
Relative partial molal enthalpies of thiourea and water
and excess of relative partial molal entropy of water were
determined from enthalpies of solution of thiourea in water with in the temperature range 293.15-333.15 K.
A new method of chromatographic paper separation of a
mixture of ions Fe(III), Cr(III) and Al(III) has been
elaborated with the use of differences of complexogenic
properties of violet R in respect of the particular ions.
By the method of ion exchange on the exchanger Dowex 50
WX 8 100-200 mesh complex formation was investigated in the
system Me(ClO₄)₃ + XC₆H₄OH + HClO₄ + NaClO₄ + H₂O, with
Me = Fe(III) or Al(III) and X = Cl, Br, CH₃, NO₂. It was
proved that 1:1 complexes are formed between Me(III) and
a phenol molecule. Stability constants of the complexes
were determined and related with Hammett’s sigma constants.
A new method of chromatographic paper was - elaborated
of separating a mixture of cations: Fe(III), Cr(III) and
Al(III) from a medium containing nitroso-R-salt (NRS) as a
complexogenic agent.
The viscosity of NaI solutions in mixed water-acetamide
solvents over the temperature range 25-85°C has been measured. The dependence of viscosity, relative viscosity
and the thermodynamic functions of activation for fluid
flow of Investigated solutions on the concentration and
temperature has been discussed. The conclusions about the
effect of NaI and acetamide on the structure of investigated...
The method were elaborated for the preparation of
[Cr(CH₃CONHCSNH₂)₃] (ClO₄)₃. In this paper we give conditions for the synthesis, composition, properties and propose
the structure of the obtained compound.
The values of the enthalpy of solution of acetophenone in methanol, butanol-1, 2-methylpropanol-1 and butanol-2 with in the concentration range from ca. 0.003 mole/kg to ca.0.043 mole/kg at 286.16 K have been determined.
It has been found that the heat of solution of acetophenone in the investigated alcohols is independent of concentration. The enthalpy of solution of acetophenone in
the investigated...
The density of aqueous acetamide solutions was measured over the temperature range 25-85 C.
From the obtained density data apparent molal volume
of acetamide in water and volume expansibility coefficient were calculated.
The analysis of changes of these functions in relation
to acetamide concentration and temperature allowed to conclude on breaking effect of acetamide on water structure.
Viscosity of NaI solutions at concentrations: 0.5, 1.0 and 2.0
mol. of electrolyte per lOO mol. of the vater-isopropanol mixed
solvents has been measured over the whole composition range at the
temperaturest 288.15, 298.15 and 313.15 K.
The course of Interaction between thiourea and trlmethylsulphoxonium
iodide in N,N-dimethylformaraide has been Investigated at
the temperature 8O°C. It haB been shown that the reaction
runs according to the kinetic equation of first-order. It has been
found that introduction of potassium iodide to the system results
in higher rate of the reaction whereas water strongly inhibits the
course of...
Ceric perchlorate, introduced to chemical analysis by Smith
and Getz [1], is increasingly applied to the titration of
both inorganic and organic compounds [2-7]. Its high oxidizing potential
(1.7 V) and the high stability of seric perchlorate solution
[1] have made it possible to develop methods of titrating
amides.
The viscosity of NaI solutions at concentrations of 0.5, 1.0
and 2.0 moles of electrolyte per 100 moles of the mixed solvent
has been measured within the whole composition range of the mixtures
of water with isobutanol, sec-butanol at 298.15 K and with
tert-butanol at 299.15 K.
The values of the solution enthalpy of benzophenone In methanol, n-buthnol, 2-methylpropanol-l and butanol-2 have been measured
within the range from ca. 0.002 mol. kg⁻¹ to ca 0.04 mol. kg⁻¹
concentration range at 286.16 K and 298.16 K. It has been found
that the solution enthalpy of benzophenone in the investigated alcohols
in the above concentration range is constant within this experimental...
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