Infrared spectra and kinetics of decomposition of primary ozonides in the liquid phase at low temperatures

The infrared spectrum of hydrazine perchlorate hemihydrate (HPH) has been determined and an assignment of the absorption bands made. Invacuo, HPH will partially dehydrate even at room temperature; when heated the remainder of the half-mole of water is lost at 61 °C. The dehydrated salt melts at 138 °C and decomposition ensues. The kinetics of decomposition may be followed in the temperature range 180–280 °C. The activation energy is 36.3 kcal/mole. At low temperatures the decomposition is represented by the chemical equation[Formula: see text]but when the temperature is high enough the rate of decomposition of the ammonium perchlorate formed becomes appreciable also. Possible reaction mechanisms are discussed.

Download Full-text

The Vibrational Spectra of α-Bromoacetaldehyde Dimethyl Acetal and Related Molecules

Applied Spectroscopy ◽

10.1366/000370275774455572 ◽

1975 ◽

Vol 29 (6) ◽

pp. 501-506 ◽

Cited By ~ 1

Author(s):

J. E. Katon ◽

Philip D. Miller

Keyword(s):

Liquid Phase ◽

Infrared Spectra ◽

Vibrational Spectra ◽

Low Temperatures ◽

Conformational Equilibrium ◽

Dimethyl Acetal ◽

Vibrational Assignment ◽

Crystal State ◽

Apparent Evidence

The complete vibrational spectra of α-bromoacetaldehyde dimethyl acetal and α-bromoacetaldehyde dimethyl s6 have been recorded on the pure liquids, and a tentative vibrational assignment has been proposed. The infrared spectra of both compounds in the crystal state have also been recorded at low temperatures. There is no apparent evidence of a conformational equilibrium in the liquid phase. The infrared spectra of three other acetals have been recorded, and the data from all of the compounds are discussed in terms of previously proposed group frequencies of acetals in both the infrared and Raman.

Download Full-text

Kinetics of liquid-liquid phase transfer catalyzed etherification of eugenol with allyl bromide: Selectivity of O- Vc C- alkylation

Catalysis in Green Chemistry and Engineering ◽

10.1615/catalgreenchemeng.2020034490 ◽

2020 ◽

Author(s):

Ganapati Yadav

Keyword(s):

Liquid Phase ◽

Allyl Bromide ◽

Phase Transfer ◽

Kinetics Of

Download Full-text

Effect of ionizing radiation on the kinetics of hydrogenation on the Ni-MgO mixed catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821780 ◽

1982 ◽

Vol 47 (7) ◽

pp. 1780-1786 ◽

Cited By ~ 2

Author(s):

Rostislav Kudláček ◽

Jan Lokoč

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Liquid Phase ◽

Ionizing Radiation ◽

Oxide Catalyst ◽

Absorbed Dose ◽

Hydrogenation Rate ◽

Solution Composition ◽

Mixed Catalyst ◽

Kinetics Of

The effect of gamma pre-irradiation of the mixed nickel-magnesium oxide catalyst on the kinetics of hydrogenation of maleic acid in the liquid phase has been studied. The changes of the hydrogenation rate are compared with the changes of the adsorbed amount of the acid and with the changes of the solution composition, activation energy, and absorbed dose of the ionizing radiation. From this comparison and from the interpretation of the experimental data it can be deduced that two types of centers can be distinguished on the surface of the catalyst under study, namely the sorption centres for the acid and hydrogen and the reaction centres.

Download Full-text

Kinetics and Mechanism of Decomposition of 1,3-Bis(4-methylphenyl)triazene Catalyzed with Substituted Benzoic Acids in 25% Aqueous Methanol-General or Specific Catalysis?

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19942029 ◽

1994 ◽

Vol 59 (9) ◽

pp. 2029-2041

Author(s):

Oldřich Pytela ◽

Taťjana Nevěčná

Keyword(s):

Benzoic Acids ◽

Hammett Equation ◽

Aqueous Methanol ◽

Mechanism Of Decomposition ◽

Kinetics Of Decomposition ◽

Independent Variable ◽

Amino Derivatives ◽

Substituted Benzoic Acids ◽

The Individual ◽

Kinetics Of

The kinetics of decomposition of 1,3-bis(4-methylphenyl)triazene catalyzed with 13 substituted benzoic acids of various concentrations have been measured in 25 vol.% aqueous methanol at 25.0 °C. The rate constants observed (297 data) have be used as values of independent variable in a series of models of the catalyzed decomposition. For the catalytic particles were considered the undissociated acid, its conjugated base, and the proton in both the specific and general catalyses. Some models presumed formation of reactive or nonreactive complexes of the individual reactants. The substituent effect is described by the Hammett equation. The statistically best model in which the observed rate constant is a superposition of a term describing the dependence on proton concentration and a term describing the dependence on the product of concentrations of proton and conjugated base is valid with the presumption of complete proton transfer from the catalyst acid to substrate, which has been proved. The behaviour of 4-dimethylamino, 4-amino, and 3-amino derivatives is anomalous (lower catalytic activity as compared with benzoic acid). This supports the presumed participation of conjugated base in the title process.

Download Full-text

Kinetics of esterification of monoisopropylphenols with phosphoryl trichloride

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19891311 ◽

1989 ◽

Vol 54 (5) ◽

pp. 1311-1317

Author(s):

Miroslav Magura ◽

Ján Vojtko ◽

Ján Ilavský

Keyword(s):

Liquid Phase ◽

Rate Constants ◽

Reaction Rates ◽

Activation Energies ◽

The Individual ◽

Kinetics Of

The kinetics of liquid-phase isothermal esterification of POCl3 with 2-isopropylphenol and 4-isopropylphenol have been studied within the temperature intervals of 110 to 130 and 90 to 110 °C, respectively. The rate constants and activation energies of the individual steps of this three-step reaction have been calculated from the values measured. The reaction rates of the two isomers markedly differ: at 110 °C 4-isopropylphenol reacts faster by the factors of about 7 and 20 for k1 and k3, respectively. This finding can be utilized in preparation of mixed triaryl phosphates, since the alkylation mixture after reaction of phenol with propene contains an excess of 2-isopropylphenol over 4-isopropylphenol.

Download Full-text

The Reactivity of Different Active Forms of Sodium Carbonate with Respect to Sulfur Dioxide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922302 ◽

1992 ◽

Vol 57 (11) ◽

pp. 2302-2308

Author(s):

Karel Mocek ◽

Erich Lippert ◽

Emerich Erdös

Keyword(s):

Thermal Decomposition ◽

Liquid Phase ◽

Sulfur Dioxide ◽

Specific Surface ◽

Surface Area ◽

Sodium Carbonate ◽

Room Temperature ◽

Active Form ◽

The Other ◽

Kinetics Of

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.

Download Full-text