THE POTENTIOMETRIC TITRATION OF CARBONATE SOLUTIONS CONTAINING URANIUM

Potentiometric titrations with hydrochloric acid were carried out on standard sodium carbonate solutions containing varying amounts of uranyl nitrate. The results confirmed the fact that uranium is present in such solutions as the complex ion [Formula: see text]. It was found that only the free CO3−− is titrated with H+ up to the first end point at pH = 8. 2. The complex ion is very stable and is decomposed only on further addition of acid when the complexed CO3−− along with the HCO3− in the solution is converted to carbonic acid before the second end point. The pH at which the second end point occurs is lowered from its normal value of 4.0 in the presence of uranium. This effect is attributed to hydrolysis of the UO2++ ion. The necessary corrections for determining carbonate and bicarbonate in the presence of uranium are given.

Download Full-text

Conductimetric and potentiometric investigation of effect of acidity on formation of homoconjugates in acetonitrile solvent

Canadian Journal of Chemistry ◽

10.1139/v90-103 ◽

1990 ◽

Vol 68 (5) ◽

pp. 674-678 ◽

Cited By ~ 3

Author(s):

Turgut Gündüz ◽

Esma Kiliç ◽

Güleren Özkan ◽

Muhammed F. Awaad ◽

Mustafa Tastekin

Keyword(s):

Carboxylic Acids ◽

Potentiometric Titration ◽

Major Part ◽

Nitrogen Atmosphere ◽

Nonaqueous Media ◽

Potentiometric Titrations ◽

End Point ◽

Titration Curves ◽

Aliphatic Carboxylic Acids ◽

Conjugate Base

In the present work, 11 aromatic and nine aliphatic carboxylic acids, namely benzoic, 2-nitrobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 2,4-dinitrobenzoic, 3,5-dinitrobenzoic, 2-aminobenzoic, 3-aminobenzoic, 4-aminobenzoic, o-phthalic, salicylic, formic, acetic, monochloroacetic, dichloroacetic, trichloroacetic, propionic, n-butyric, caprylic, and myristic acids, were titrated conductimetrically and potentiometrically with triethylamine in acetonitrile solvent, under a nitrogen atmosphere, at 25 °C. Closer investigation of the conductimetric titration curves of these acids showed that the acidity of an acid, rather than the basicity of its conjugate base, plays a major part in the formation of homoconjugate ions, at least in acetonitrile solvent. If the acid is strong enough, there is a maximum before the experimental end point at about the half-neutralization point. To determine the minimum strength for an acid to show this maximum before the end point, all acids were also titrated potentiometrically. It was found that those acids which have half-neutralization potentials over −85 mV give a strong homoconjugation reaction and show a maximum before the experimental end point. Moreover, the acids that show maxima before the experimental end point in the conductimetric titration also show rather well-shaped potentiometric titration curves. Keywords: nonaqueous media, conductimetric titrations, potentiometric titrations, titration in acetonitrile, acidity and homoconjugation.

Download Full-text

Alteration of smectites by treatments with hydrochloric acid and sodium carbonate solutions

Applied Clay Science ◽

10.1016/0169-1317(90)90017-j ◽

1990 ◽

Vol 5 (2) ◽

pp. 113-122 ◽

Cited By ~ 61

Author(s):

Peter Komadel ◽

Dieter Schmidt ◽

Jana Madejová ◽

Blahoslav C̆íc̆el

Keyword(s):

Hydrochloric Acid ◽

Sodium Carbonate ◽

Carbonate Solutions

Download Full-text

XV.—Studies of the carbonates. Part II. Hydrolysis of sodium carbonate and bicarbonate and the ionisation constants of carbonic acid

Journal of the Chemical Society Transactions ◽

10.1039/ct9171100138 ◽

1917 ◽

Vol 111 (0) ◽

pp. 138-158 ◽

Cited By ~ 3

Author(s):

Clarence Arthur Seyler ◽

Percy Vivian Lloyd

Keyword(s):

Sodium Carbonate ◽

Carbonic Acid ◽

Hydrolysis Of

Download Full-text

Enthalpies of dilution of sodium carbonate and sodium hydrogen carbonate solutions, and the standard enthalpies of ionization of aqueous carbonic acid, at 298.15 K

The Journal of Chemical Thermodynamics ◽

10.1016/0021-9614(78)90080-0 ◽

1978 ◽

Vol 10 (11) ◽

pp. 1049-1075 ◽

Cited By ~ 25

Author(s):

Robert L Berg ◽

Cecil E Vanderzee

Keyword(s):

Sodium Carbonate ◽

Sodium Hydrogen Carbonate ◽

Carbonic Acid ◽

Enthalpies Of Dilution ◽

Sodium Hydrogen ◽

Carbonate Solutions ◽

Hydrogen Carbonate

Download Full-text

Reaction of metallic nitrilotriacetates with histamine

Canadian Journal of Chemistry ◽

10.1139/v69-211 ◽

1969 ◽

Vol 47 (8) ◽

pp. 1269-1273 ◽

Cited By ~ 9

Author(s):

A. L. Beauchamp ◽

J. Israeli ◽

H. Saulnier

Keyword(s):

Potentiometric Titration ◽

Formation Constants ◽

Amino Group ◽

Mixed Complex ◽

Ph Values ◽

Titration Curves ◽

Terminal Amino ◽

Complex Ion

Cu(II), Ni(II), Co(II), and Zn(II) nitrilotriacetates (MeX−) react with histamine nitrate (LH+) to form a protonated mixed complex MeXLH where the metal appears to be bound only to the tertiary imidazolic nitrogen of histaminium ion. At higher pH values the proton dissociates to yield a mixed complex ion MeXL− in which both the imidazolic nitrogen and the terminal amino group are coordinated. The formation constants of these species were calculated from the potentiometric titration curves.

Download Full-text

Some Experiments on the Extra-Corporeal Hatching of the Eggs of Ascaris suum

Journal of Helminthology ◽

10.1017/s0022149x00031084 ◽

1939 ◽

Vol 17 (2) ◽

pp. 69-82 ◽

Cited By ~ 3

Author(s):

D. W. Fenwick

Keyword(s):

Hydrochloric Acid ◽

Digestive Tract ◽

Sodium Carbonate ◽

Ascaris Suum ◽

The Body ◽

Very Old ◽

The Past ◽

Pancreatic Fluid ◽

Sand Cultures ◽

Made In

Numerous attempts have been made in the past to induce the eggs of Ascaris suum to hatch outside the body of the host. Extra-corporeal hatching has been observed under a variety of conditions by different workers. Kondo (1920, 1922), Asada (1921) and others record hatching in water, charcoal and sand cultures. Wharton (1915) states that hatching will occur in alkaline digestive juices, while Martin (1913) records a similar phenomenon in pancreatic fluid. Many different explanations have been offered to explain this hatching. Wharton suggested that the interaction of algae and sand might have some effect. Ohba (1923), who found that hatching would occur in 0·2% hydrochloric acid and 0·2% sodium carbonate believed that extra-corporeal hatching was limited to very old cultures of eggs. Many workers are of the opinion that some stimulus normally present in the digestive tract is necessary for hatching.

Download Full-text

The synthesis of Cyclododecane-r-1,c-5,c-9-triamine and r-1,c-5,c-9-Tris(2,3-dimethoxybenzamido)cyclododecane

Australian Journal of Chemistry ◽

10.1071/ch9750673 ◽

1975 ◽

Vol 28 (3) ◽

pp. 673 ◽

Cited By ~ 5

Author(s):

DJ Collins ◽

C Lewis ◽

JM Swan

Keyword(s):

Aqueous Solution ◽

Acid Hydrolysis ◽

Sulphuric Acid ◽

Sodium Carbonate ◽

Sodium Azide ◽

Room Temperature ◽

Dimethyl Formamide ◽

Lithium Aluminium Hydride ◽

Lithium Aluminium ◽

Hydrolysis Of

Treatment of cyclododecane-r-1,c-5,c-9-triyl tris(p-toluenesulphonate) with sodium azide in dimethyl-formamide at 100� for 6 h gave the corresponding cis,cis-triazide which upon hydrogenation or reduction with lithium aluminium hydride gave cyclododecane-r-1,c-5,c-9-triamine, isolated as the tris-salicylidene derivative. Acid hydrolysis of this, removal of the salicylaldehyde, and treatment of the aqueous solution with sodium carbonate and 2,3-dimethoxybenzoyl chloride gave r-1,c-5,c- 9-tris(2,3-dimethoxybenzamido)cyclododecane. �� Treatment of (E,E,E)-cyclododeca-1,5,9-triene with an excess of acetonitrile and sulphuric acid at room temperature for three days gave 18% of (E,E)-1-acetamidocyclododeca-4,8-diene; no di- or tri-amides were isolated.

Download Full-text