Hydrolysis of diethyl benzoylphosphonate in aqueous and hydrochloric acid solutions. Postulation of a stable pentavalent phosphorus-containing intermediate

1979 ◽  
Vol 101 (1) ◽  
pp. 109-116 ◽  
Author(s):  
K. S. Narayanan ◽  
K. D. Berlin
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solutions ◽  
Pentavalent Phosphorus ◽  
Hydrochloric Acid Solutions ◽  
Phosphorus Containing ◽  
Hydrolysis Of

Kajian potensi limbah tulang sirip Ikan Tuna (Thunnus Sp) sebagai sumber gelatin dan analisis karakteristiknya

Jurnal Zona ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 50-57
Author(s):  
Dahlia Dahlia ◽  
Rahman Karnila ◽  
Yusni Ikhwan Siregar
Keyword(s):  
Hydrochloric Acid ◽  
Food Studies ◽  
Bone Collagen ◽  
Acid Solutions ◽  
Fishy Odor ◽  
Hydrochloric Acid Solutions ◽  
Hydrolysis Of

Gelatin is a protein from the hydrolysis of bone collagen and skin of animals wich are widely used for industrial food and non food. Studies on extraction of gelatin from tuna (Thunnus sp) bone were carried out by soaking in hydrochloric acid solutions of 4%, 6% and 8% for 48 hours respectivelly and extracted with aquadest at 60ºC, 70ºC and 80ºC for 5 hours. The extract was filtered with filtering cloth and the filtrate was oven dried at 55ºC for ± 48 hours until gelatin was formed. The result showed that soaking the bone in 8% hydrochloric acid solutions followed by extraction 80ºC for 5 hours gave the best result with 8,64 yield, isoelectrict point 8,20%, protein contain 93,72%, lipid contain 0,74-1,75%. Gel strengh 257,59 g/bloom gel strengh, viscosity 3,20 cPs, pH 3,98. The results obtained for water contain of 6,97%. Ash countain 2,07%. The colour of gelatin produced from tuna bone showered different with commercial gelatin that is between yellowish brown to whitish yellow. Gelatin made from tuna bone has fishy odor whereas commercial gelatin has neutral odor.

THE HYDROLYSIS OF ACID AMIDES IN CONCENTRATED HYDROCHLORIC ACID SOLUTIONS

1942 ◽  
Vol 20b (5) ◽  
pp. 73-81 ◽  
Author(s):  
B. S. Rabinovitch ◽  
C. A. Winkler
Keyword(s):  
Activation Energy ◽  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Reaction Rates ◽  
Activation Energies ◽  
Acid Solutions ◽  
Hydrochloric Acid Solutions ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of

The Arrhenius constants have been evaluated for the hydrolysis of formamide, acetamide, propionamide, and benzamide in hydrochloric acid solutions over the concentration range 1 to 10 N. There is approximate correspondence between reaction rates and activation energies for the series of amides. An increase in observed activation energy with increasing acid concentration was found for all amides. The maximum in rate of hydrolysis, which occurs at higher acid concentrations, is discussed and accounted for by the variation in the Arrhenius constants with acid concentration.

A Comparison of the H_ and H0 Acidity Functions for Aqueous Hydrochloric Acid Solutions

1961 ◽  
Vol 14 (2) ◽  
pp. 183 ◽  
Author(s):  
JN Phillips
Keyword(s):  
Hydrochloric Acid ◽  
Acidity Function ◽  
Acid Solutions ◽  
Aqueous Hydrochloric Acid ◽  
Neutral Base ◽  
Hydrochloric Acid Solutions ◽  
Phosphorus Containing ◽  
Strong Acidity ◽  
Acidity Functions ◽  
The Relationship

H- acidity function measurements are reported for aqueous hydrochloric acid solutions using a series of phosphorus-containing acid indicators. The relationship between the H-, Ho, and activity (-log10f�C) function for this system was found to be given approximately by ����������������� �(Ho+H-) ≈ -log10f�CHCl A feature of the results is the weak acidity of concentrated hydrochloric acid solutions in respect of the ionization of a negatively charged base, in contrast to the strong acidity of such solutions in respect of the ionization of a neutral base.

The acid-catalyzed hydrolysis of methyl 2-chloro-2-deoxy-β-D-glucopyranoside

1967 ◽  
Vol 45 (5) ◽  
pp. 515-519 ◽  
Author(s):  
E. Buncel ◽  
P. R. Bradley
Keyword(s):  
Hydrochloric Acid ◽  
Acid Solutions ◽  
Hydrochloric Acid Solutions ◽  
Mechanism Of Hydrolysis ◽  
Entropy Of Activation ◽  
Acid Catalyzed ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of the hydrolysis of methyl 2-chloro-2-deoxy-β-D-glucopyranoside have been determined in hydrochloric acid solutions over a range of acid concentrations and temperatures. Chloro substitution reduces the rate by a factor of 35 compared with the hydroxy analogue. Application of the Hammett criterion indicates a unimolecular (A-1) mechanism of hydrolysis, as does application of the Bunnett criterion. The entropy of activation, however, is considerably smaller than that observed for the hydrolysis of methyl β-d-glucopyranoside. This is interpreted as being indicative of partial A-2 character.

THE HYDROLYSIS OF PROPIONITRILE IN CONCENTRATED HYDROCHLORIC ACID SOLUTIONS

1942 ◽  
Vol 20b (7) ◽  
pp. 121-132 ◽  
Author(s):  
B. S. Rabinovitch ◽  
C. A. Winkler ◽  
A. R. P. Stewart
Keyword(s):  
Activation Energy ◽  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Acid Solutions ◽  
Large Measure ◽  
Unimolecular Reactions ◽  
Hydrochloric Acid Solutions ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Ammonia Formation

The hydrolysis of propionitrile has been studied in aqueous hydrochloric acid solutions from 0.5 to 10 N and over a range of temperatures at six acid concentrations. The rate of hydrolysis as measured by ammonia formation is dependent upon the decomposition of the intermediate amide at acid concentrations above 4 N. The system represented by nitrile [Formula: see text] amide [Formula: see text] acid affords a good example of consecutive, irreversible unimolecular reactions over the complete range [Formula: see text] (below 4 N) to [Formula: see text] (above 11 N). A marked increase in rate with increasing acid concentration is accounted for in large measure by a decrease in observed activation energy of 6.7 Cal. over the range 1 to 10 N.

THE HYDROLYSIS OF ALIPHATIC NITRILES IN CONCENTRATED HYDROCHLORIC ACID SOLUTIONS

1942 ◽  
Vol 20b (10) ◽  
pp. 221-230 ◽  
Author(s):  
B. S. Rabinovitch ◽  
C. A. Winkler
Keyword(s):  
Activation Energy ◽  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Hydrocyanic Acid ◽  
Acid Solutions ◽  
Acid Media ◽  
Hydrochloric Acid Solutions ◽  
Aliphatic Nitriles ◽  
Nitrile Hydrolysis ◽  
Hydrolysis Of

Studies of nitrile hydrolysis in concentrated acid media have been extended to the hydrolysis of hydrocyanic acid, acetonitrile, and cyanoacetic acid in hydrochloric acid solutions of concentration 1 to 8.5 N. It appears that the hydrolysis of aliphatic nitriles in concentrated sulphuric and hydrochloric acids provides systems of consecutive, irreversible unimolecular reactions over the complete range knitrile[Formula: see text]kamide (more dilute acid) to knitrile[Formula: see text]kamide (highly concentrated acid), for a sufficient range of acid concentrations. The limit, knitrile[Formula: see text]kamide, is not attained in hydrobromic acid solutions. The nitriles studied here exhibit a large decrease in activation energy with increase of acid concentration, similar to that observed earlier for propionitrile. The magnitude of the variation of the Arrhenius parameters is specific for each nitrile. For the acetonitrile hydrolysis, the increase in rate with increase of acid concentration largely follows the accompanying activation energy decrease. The relative rates of hydrolysis of different nitriles, at given acid concentration, are not governed by differences in activation energy. The variation of activation energy is briefly discussed in relation to certain other factors.

Untersuchungen über die Kinetik der Spaltung von Di- und Tripeptiden

1964 ◽  
Vol 19 (12) ◽  
pp. 1095-1100 ◽  
Author(s):  
Hermann Hartmann ◽  
Joachim Heidberg
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Freeze Drying ◽  
Proteolytic Enzymes ◽  
Pure Water ◽  
Peptide Bond ◽  
Nucleophilic Attack ◽  
Acid Solutions ◽  
Hydrochloric Acid Solutions ◽  
Hydrolysis Of

The kinetic data of the hydrolysis of some serine peptides in diluted hydrochloric acid and in pure water and of the rearrangement of O-glycyl-DL-serine to glycyl-DL-serine were determined.The hydrolysis of glycyl-DL-serine and DL-alanyl-DL-serine proceeds surprisingly rapidly in pure water as compared with the hydrolysis of those peptides in 0.5 N hydrochloric acid as well as the hydrolysis of glycyl-DL-alanine in purely aqueous solution. The O → N migration of the glycyl residue in O-glycyl-DL-serine which probably is an intermediate in the cleavage of glycyl-DL-serine in purely aqueous solution represents a three center reaction in which the nucleophilic attack on the O-peptide and peptide bond, respectively, involves a free basic amino group. The analogy between the serine peptide interconversion and the hydrolysis catalyzed by certain proteolytic enzymes is referred to.Under the conditions of freeze drying are formed in hydrochloric acid solutions of DL-alanyl-DL-serine O-peptide and depsipeptide.

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