THE DECOMPOSITION OF CHLOROACETIC ACID IN AQUEOUS SOLUTIONS BY ATOMIC HYDROGEN. II. REACTION MECHANISM IN ALKALINE SOLUTIONS

1962 ◽  
Vol 66 (11) ◽  
pp. 2081-2084 ◽  
Author(s):  
Joshua Jortner ◽  
Joseph Rabani
Keyword(s):  
Reaction Mechanism ◽  
Aqueous Solutions ◽  
Atomic Hydrogen ◽  
Chloroacetic Acid ◽  
Alkaline Solutions

scholarly journals Investigation on the Effect of Addition of Fe3+ Ion into the Colloidal AgNPs in PVA Solution and Understanding Its Reaction Mechanism

2017 ◽  
Vol 17 (3) ◽  
pp. 439 ◽  
Author(s):  
Roto Roto ◽  
Marcelina Marcelina ◽  
Nurul Hidayat Aprilita ◽  
Mudasir Mudasir ◽  
Taufik Abdillah Natsir ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Reaction Mechanism ◽  
Polyvinyl Alcohol ◽  
Aqueous Solutions ◽  
Surface Plasmon ◽  
Ag Nanoparticles ◽  
Capping Agents ◽  
Colorimetric Methods

Analysis of Fe3+ ion present in aqueous solutions is always of interests. Recently, this ion has been analyzed by colorimetric methods using colloid of silver nanoparticles (AgNPs) in capping agents of polymers. The reaction mechanism between AgNPs and Fe3+ is still subject to the further investigation. In this work, 1,10-phenanthroline was used to probe the reaction mechanism between AgNPs and Fe3+ ion in the solution. The colloids of AgNPs were prepared in the polyvinyl alcohol (PVA) solution and reacted with Fe3+. The colloid surface plasmon absorbance decreases linearly along with the increase in Fe3+ concentration. The addition of 1,10-phenanthroline to mixture changes the solution to red, indicating that the reaction produces Fe2+. This suggests that the reduction of the AgNPs absorbance is the result of oxidation of the Ag nanoparticles along with the reduction of Fe3+.

scholarly journals Formation of carboxylic acids during degradation of monosaccharides

2008 ◽  
Vol 26 (No. 2) ◽  
pp. 113-131 ◽  
Author(s):  
O. Novotný ◽  
K. Cejpek ◽  
J. Velíšek
Keyword(s):  
Free Radicals ◽  
Aqueous Solutions ◽  
Carboxylic Acids ◽  
Sodium Hydroxide Solution ◽  
Model Systems ◽  
Alkaline Solutions ◽  
Hydroxycarboxylic Acids ◽  
Acid Type ◽  
Cannizzaro Reaction ◽  
Benzilic Acid

The formation of low molecular carboxylic and hydroxycarboxylic acids as well as sugar and deoxysugar acids from monosaccharides (D-glucose, D-fructose, D-arabinose, DL-glyceraldehyde, and 1,3-dihydroxyacetone) was studied in three different model systems: aqueous and alkaline solutions of potassium peroxodisulfate (K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>), and sodium hydroxide solution. In total, 3 low molecular carboxylic acids (formic, acetic and propionic), 24 hydroxycarboxylic acids, and 12 corresponding lactones were identified and quantified by GC/MS. Formic, acetic, and propionic acids were isolated by extraction with diethyl ether and directly analysed by GC/MS; hydroxycarboxylic acids and their lactones were monitored as their trimethylsilylated derivatives using the same method. Formic, acetic, L-lactic, glycollic, DL-2,4-dihydroxybutanoic acids and aldonic acids derived from the parent sugars were the most abundant compounds in all model systems. Within the models investigated, the yield of carboxylic acids and hydroxycarboxylic acids (together with their lactones) ranged between 9.3–22.2% (n/n) and between 3.6–116.9% (n/n), respectively. The amount of acids was significantly lower in aqueous solutions of K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> than in the alkaline solutions. The data obtained indicate that lower carboxylic acids are formed by both subsequent reactions (oxidation and/or intramolecular Cannizzaro reaction) of the sugar fragmentation products and direct decomposition of some intermediates such as uloses or hydroperoxides derived from the parent sugars. The acids possessing the original sugar skeleton are formed as a result of sugar oxidation or benzilic acid type rearrangement of deoxyuloses. Lower acids may also be formed by a recombination of free radicals.

THE RADIOLYSIS OF ALKALINE AQUEOUS SOLUTIONS CONTAINING HYDROGEN AND OXYGEN

1966 ◽  
Vol 44 (6) ◽  
pp. 737-741 ◽  
Author(s):  
W. A. Armstrong
Keyword(s):  
Reaction Mechanism ◽  
Radical Reactions ◽  
Alkaline Solutions ◽  
Oh Radicals ◽  
Neutral Solution ◽  
A Value ◽  
Rate Of Reaction ◽  
Γ Rays ◽  
Ph Range ◽  
The Relationship

The initial yields of H2O2 in aerated water, [Formula: see text] and in water containing H2 and O2, [Formula: see text] have been measured for alkaline solutions irradiated with 60Co γ-rays. [Formula: see text] decreases with increasing pH from a value of 1.22 in neutral solution to 0.63 in solutions of pH 13.92 and the relationship[Formula: see text]is valid over the pH range 7 to 14.[Formula: see text] decreases from 3.30 in neutral solution to a minimum of 2.00 at pH 11.35 and then increases to 2.65 at pH 13.92. The equation[Formula: see text]which is applicable for neutral solutions, is not valid for basic solutions.A reaction mechanism in accordance with the observed results and the literature values of the rate constants of likely radical reactions has been developed. It is assumed that in the alkaline solutions investigated OH radicals react with OH− ions to form O− radicals which react preferentially with O2 to form O3− radicals which then react either with H2 or H2O2. The increase in [Formula: see text] at PH > 12 is attributed to a difference in the rate of reaction of O3− with H2O2 and HO2−, k(O3− + H2O2)/k(O3− + HO2−) = 2.45.

The Action of Atomic Hydrogen on Aqueous Solutions: I. Effect on Silver, Cysteine, and Glutathione Solutions

1957 ◽  
Vol 7 (2) ◽  
pp. 107 ◽  
Author(s):  
F. E. Littman ◽  
E. M. Carr ◽  
A. P. Brady
Keyword(s):  
Aqueous Solutions ◽  
Atomic Hydrogen
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