Introduction a l'étude des sels basiques insolubles: Étude des courbes de précipitation des sels basiques insolubles. Produits de solubilité des sels basiques et des hydroxydes

A critical study of curves of precipitation of basic salts by alkali hydroxides shows that the irregularities observed on these curves do not always permit the deduction of the constitution of the salt. They indicate nevertheless the appearance of a new phase and this observation explains, in particular, the important number of wrongly defined basic salts which have been observed.The theory of the titre curves leads to the proposal of formulas permitting the calculation of solubility products of basic salts and even those of hydroxides which were determined very accurately by other methods.     

Contribution a l'étude de la standardisation des solutions acides normales: Utilisation de l'hydrogénocarbonate de sodium comme substance de référence

Experiments have shown that it is not advisable to use the crude product of the calcination of sodium bicarbonate as a standardization substance in acidimetry.     

Dosages en analyse minérale par extraction à l'aide de cations colorés: Dosages par extraction a l'aide de colorants basiques b. dosage de traces d'étain par le violet cristallisé

An extraction method is described for the determination of traces of tin in which crystal violet is used as complexing agent.     

Dosages en analyse minérale par extraction à l'aide de cations colorés : Dosages par extraction à l'aide de colorants basiques c. dosage de traces de phosphate par la safranine

An extraction method is described for the determination of traces of phosphate in the form of phosphomolybdate, in which safranine is used as complexing agent.     

Sur la thermogravimétrie des précipités analytiques : Dosage de l'yttrium

The thermolysis curves of yttrium hydroxide and oxalate are described.     

Sur la thermogravimétrie des précipités analytiques: Dosage de l'uranium

A study has been made of the gravimetric methods for the determination of 4- and 6-valent uranium and two new forms of weighing are suggested, as oxalate and anhydrous oxmate. The following table summarizes the temperature limits, determined by means of the Chevenard thermobalance, for various precipitates:

     

7.

Étude de la rétention des sels monovalents et bivalents par nanofiltration     

《Comptes Rendus Chimie》2003,6(4):431-436

Study of the retention of monovalent and bivalent salts by nanofiltration. The objective of this work was to study the influence of applied pressure, solution concentration and conversion rate on the salts retention by nanofiltration. Our study showed that the bivalent ions SO₄^2– are better retained than the monovalent ions F^–, Cl^– and I^– by nanofiltration. We also observed that the small ions F^– and Mg²⁺ are better retained than the big ions Cl^–, Ca²⁺, and I^– by effect of solvation. In spite of the bigger size of ion Ba²⁺ compared to Ca²⁺, Ba²⁺ is better retained than Ca²⁺; this is due to the effect of pressure. We also noticed that the increase of the (NH₄)₂SO₄ concentration and of the conversion rate leads to a decrease in the retention of SO₄^2–. To cite this article: A. Abouzaid et al., C. R. Chimie 6 (2003).     

8.

Sur la thermogravimétrie des précipités analytiques: Dosage de l'lridium     

Clément Duval  Pierre Champ  Pierre Fauconnier 《Analytica chimica acta》1959

Thermolysis curves have been recorded of precipitates containing iridium, obtained with formic acid, 2-mercapto-benzothiazole and sodium sulphide respectively.     

9.

Dosages en analyse minérale par extraction à l'aide de cations colorés: Dosages par extraction à l'aide de colorants basiques a. dosage de traces d'or pàr le violet de méthyle en présence de platine     

Lucien Ducret  Henri Maurel 《Analytica chimica acta》1959

     

10.

Dosages en analyse minérale par extraction à l'aide de cations colorés : Dosages par extraction a l'aide de colorants basiques d. dosage de traces de sulfate par le bleu de méthylène     

Lucien Ducret  Michèle Ratouis 《Analytica chimica acta》1959

A method is described for the determination of traces of sulphate. By means of an exchange resin the sulphate ions are exchanged with an equivalent amount of thiocyanate ions and these are determined by the extraction method using methylene blue as complexing agent.     

11.

Dosage de l'histidine: Étude polarographique et dosage du dinitrofluorobenzene     

P.E Wenger  D Monnier  S Faraggi 《Analytica chimica acta》1955

After polarographic study and determination of dinitrofluorobenzene at varying pH and determination of a number of electron exchanges (n), standardization curves have been constructed at pH 5 and 10. They allow the estimation of DNFB to a concentration of 1γ/ml with a precision of 4–7%. The curve shows 2 or 3 leaps, according to pH.. The E_{$\text{1}\text{2}$} of the first two are less than 1 volt.     

12.

Réduction électrochimique de l'eau et de ses ions : Cas des acides faibles et des mélanges tampons     

《Analytica chimica acta》1957

We have verified that, using a platinized platinum electrode, the polarization curves of solutions of weak acids or buffer mixtures can be interpreted, assuming the existence of an electrochemical reaction of the type: 2 HA + 2 e ? H₂ + 2A^-This reaction can be considered as the sum of twodistinctreactions, one electrochemical reduction of free H⁺ the other chemical acid-base equilibrium.Assuming th.it (i) the oxidation-reduction system H;g/H+ is rapid in the presence of platmiycd platinum, and (2) the laws of chemical equilibrium liold in the vicinity of the electrode, we have been able to give an account of the experimental results obtained.     

13.

Sur le noircissement des précipités de sels d'argent     

Clément Duval 《Mikrochimica acta》1956,44(9):1430-1431

Sans résumé     

14.

Étude de réactions à l'état solide entre l'arbre de Saturne et des sels contenant le groupement XO3     

Mireille Harmelin  Clément Duval 《Mikrochimica acta》1964,52(2-4):211-215

Résumé Le plomb utilisé sous forme d'arbre de Saturne possède une grande réactivité et permet de réduire les nitrates en nitrites. Il s'agit d'une réaction à l'état solide, débutant dès la température ordinaire. On a pu caractériser ainsi la présence de nitrites en mélangeant le plomb avec les nitrates de lithium, sodium, potassium, césium, cuivre, argent, magnésium, calcium, strontium, baryum, zinc, thallium, plomb, cobalt et nickel.

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Summary Lead used in the form of the lead tree has great reactivity and is able to reduce nitrates to nitrites. This involves a solid state reaction and starts at room temperature. In this way it is possible to detect the presence of nitrites after mixing the lead with the following nitrates — Li, Na, K, Cs, Cu, Ag, Mg, Ca, Sr, Ba, Zn, Tl, Pb, Co, Ni.

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Zusammenfassung In der Form des Bleibaumes ist Pb sehr reaktionsfähig und reduziert Nitrat zu Nitrit. Dabei handelt es sich um eine Festkörperreaktion, die bei gewöhnlicher Temperatur einsetzt. Nach Vermengen von Blei mit den Nitraten von Li, Na, K, Cs, Cu, Ag, Mg, Ca, Sr, Ba, Zn, Th, Pb, Co und Ni konnte die Anwesenheit von Nitrit festgestellt werden.

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En l'honneur du ProfesseurA. A. Benedetti-Pichler, pour son 70^e anniversaire.     

15.

Influence de la cinétique des réactions chimiques sur les courbes de polarisation : Application à l'étude des complexes thiocyanés du titane(iv) et du titane(III)     

S. Tribalat  D. Delafosse 《Analytica chimica acta》1958

The electrochemical oxidation-reduction of the system titanium(IV) — titanium(III) is slow at dropping mercury electrode in perchloric acid or hydrochloric acid, but becomes rapid in the presence of thiocyanate ions.On the basis of polarization curves, interpreted according to a preliminary theoretical study, the authors conclude that the rapid electrochemical reaction is the following: TiOH.SCN⁺² + H⁺ + e ? TiSCN⁺² + H₂OAn application of the findings to the polarographic determination of titanium is given.     

16.

Séparation et dosage de traces de sodium contenues dans des sels de potassium     

Angot  J. 《Mikrochimica acta》1959,47(3):346-356

Résumé Pour séparer et doser les traces de sodium dans les sels de potassium, l'auteur fait appel à deux techniques relativement récentes: la chromatographie sur échangeurs d'ions, la photométrie de flamme.La chromatographie permet de se trouver dans des conditions idéales pour la photométrie de flamme (un seul cation, un seul anion).Il est possible, en s'entourant de précautions indispensables, de doser 0,001% de sodium à ± 10%, grâce à la sensibilité de la photométrie de flamme, et ceci, malgré l'extrême simplicité de l'appareil utilisé.

---

Summary To separate and determine traces of sodium in potassium salts, the author used two relatively recent techniques: chromatography on ion exchangers, and flame photometry.The chromatography made it possible to discover ideal conditions for the flame photometry (a single cation, one anion).It is possible, by providing certain indispensable precautions, to determine 0.001% of sodium within ± 10%, thanks to the sensitivity of the flame photometry, and even so, despite the extreme simplicity of the apparatus required.

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Zusammenfassung Zur Trennung und Bestimmung von Natriumspuren in Kaliumsalzen werden die Ionenaustauschchromatographie und die Flammenphotometrie verwendet. Die Chromatographie ermöglicht die Einhaltung der für die Flammenphotometrie bestgeeigneten Bedingungen: je ein Kation und ein Anion. Bei Beachtung der angegebenen Arbeitsvorschriften läßt sich dank der Empfindlichkeit der Flammenphotometrie trotz größter Einfachheit der verwendeten Geräte 0,001% Natrium mit einer Genauigkeit von ±10% bestimmen.

     

17.

Étude de la photolyse de sels de sulfonium,photoamorceurs cationiques     

《Comptes Rendus de l''Academie des Sciences Series IIB Mechanics Physics Astronomy》1998,1(3):201-207

Arylonium salts allowed the development of cationic photopolymerization. A number of reports about the photolysis of triarylsulfonium salts can now be found in the literature. These works deal with salt photofragmentation kinetics, the visualization of the photolysis process by real time pH mesurements and with the acid photoliberation kinetics by potentiometric titrations.     

18.

Contribution à l'étude des méthodes de dosages électrotitrimétriques     

G. Duyckaerts 《Analytica chimica acta》1953

The author establishes a general equation for the polarisation curve of an oxidation-reduction system taking into account the kinetics of reactions and concentration polarisation, and shows how it can be applied to the interpretation of titration curves obtained by the dead-stop end-point method of Foulk and Bawden and by the derivative method of Reilley, Cooke and Furman.     

19.

Utilisation de l'acide phénylarsonique en turbidimétrie: Dosage du tantale     

R. Saint-James  T. Lecomte 《Analytica chimica acta》1961

A turbidimetric method is described for the determination of tantalum with phenylarsonic acid. The method is fast and rarely requires preliminary separation. The only interfering elements are zirconium and niobium when present in molar ratios greater than Nb : Ta = 1 and Zr : Ta = 5.     

20.

Étude de différents modes de tracés et d'enregistrement des courbes de polarisation     

《Analytica chimica acta》1957

     

Precipitating reagent	Form in which weighed	Temperature limits
Ammonium hydroxide	UO3	480–610°
Ammonium hydroxide	U3O8	745–946°
Ammoniac (gas)	U3O8	675–946°
Pyridine	U3O8	745–946°
Ammonium benzoate	U3O8	691–946°
Hexamethylenetetramine	U3O8	745–946°
Tannin	U3O8	570–878°
Hydrogen peroxide	U3O8	811–946°
Hydrofluoric acid	U3O8	811–946°
Ammonium sulphate	U3O8	850–946°
Disodium phosphate	U2P2O11	673–946°
Oxalic acid	U(C2O4)2	100–180°
Oxalic acid	U3O8	700–946°
Cupferron	U3O8	800–946°
β-Isatoxime	U3O8	408–946°
8-Hydroxyquinoline	HUO2(C9H6ON)3	< I57°
8-Hydroxyquinoline	UO2(C9H6ON)2	252–346°
Quinaldinic acid	U3O8	610–946°

Étude de la rétention des sels monovalents et bivalents par nanofiltration

Study of the retention of monovalent and bivalent salts by nanofiltration. The objective of this work was to study the influence of applied pressure, solution concentration and conversion rate on the salts retention by nanofiltration. Our study showed that the bivalent ions SO₄^2– are better retained than the monovalent ions F^–, Cl^– and I^– by nanofiltration. We also observed that the small ions F^– and Mg²⁺ are better retained than the big ions Cl^–, Ca²⁺, and I^– by effect of solvation. In spite of the bigger size of ion Ba²⁺ compared to Ca²⁺, Ba²⁺ is better retained than Ca²⁺; this is due to the effect of pressure. We also noticed that the increase of the (NH₄)₂SO₄ concentration and of the conversion rate leads to a decrease in the retention of SO₄^2–. To cite this article: A. Abouzaid et al., C. R. Chimie 6 (2003).     

Sur la thermogravimétrie des précipités analytiques: Dosage de l'lridium

Thermolysis curves have been recorded of precipitates containing iridium, obtained with formic acid, 2-mercapto-benzothiazole and sodium sulphide respectively.     

Dosages en analyse minérale par extraction à l'aide de cations colorés : Dosages par extraction a l'aide de colorants basiques d. dosage de traces de sulfate par le bleu de méthylène

A method is described for the determination of traces of sulphate. By means of an exchange resin the sulphate ions are exchanged with an equivalent amount of thiocyanate ions and these are determined by the extraction method using methylene blue as complexing agent.     

Dosage de l'histidine: Étude polarographique et dosage du dinitrofluorobenzene

After polarographic study and determination of dinitrofluorobenzene at varying pH and determination of a number of electron exchanges (n), standardization curves have been constructed at pH 5 and 10. They allow the estimation of DNFB to a concentration of 1γ/ml with a precision of 4–7%. The curve shows 2 or 3 leaps, according to pH.. The E_{$\text{1}\text{2}$} of the first two are less than 1 volt.     

Réduction électrochimique de l'eau et de ses ions : Cas des acides faibles et des mélanges tampons

We have verified that, using a platinized platinum electrode, the polarization curves of solutions of weak acids or buffer mixtures can be interpreted, assuming the existence of an electrochemical reaction of the type: 2 HA + 2 e ? H₂ + 2A^-This reaction can be considered as the sum of twodistinctreactions, one electrochemical reduction of free H⁺ the other chemical acid-base equilibrium.Assuming th.it (i) the oxidation-reduction system H;g/H+ is rapid in the presence of platmiycd platinum, and (2) the laws of chemical equilibrium liold in the vicinity of the electrode, we have been able to give an account of the experimental results obtained.     

Sur le noircissement des précipités de sels d'argent

Sans résumé     

Étude de réactions à l'état solide entre l'arbre de Saturne et des sels contenant le groupement XO3

Résumé Le plomb utilisé sous forme d'arbre de Saturne possède une grande réactivité et permet de réduire les nitrates en nitrites. Il s'agit d'une réaction à l'état solide, débutant dès la température ordinaire. On a pu caractériser ainsi la présence de nitrites en mélangeant le plomb avec les nitrates de lithium, sodium, potassium, césium, cuivre, argent, magnésium, calcium, strontium, baryum, zinc, thallium, plomb, cobalt et nickel.

---

Summary Lead used in the form of the lead tree has great reactivity and is able to reduce nitrates to nitrites. This involves a solid state reaction and starts at room temperature. In this way it is possible to detect the presence of nitrites after mixing the lead with the following nitrates — Li, Na, K, Cs, Cu, Ag, Mg, Ca, Sr, Ba, Zn, Tl, Pb, Co, Ni.

---

Zusammenfassung In der Form des Bleibaumes ist Pb sehr reaktionsfähig und reduziert Nitrat zu Nitrit. Dabei handelt es sich um eine Festkörperreaktion, die bei gewöhnlicher Temperatur einsetzt. Nach Vermengen von Blei mit den Nitraten von Li, Na, K, Cs, Cu, Ag, Mg, Ca, Sr, Ba, Zn, Th, Pb, Co und Ni konnte die Anwesenheit von Nitrit festgestellt werden.

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En l'honneur du ProfesseurA. A. Benedetti-Pichler, pour son 70^e anniversaire.     

Influence de la cinétique des réactions chimiques sur les courbes de polarisation : Application à l'étude des complexes thiocyanés du titane(iv) et du titane(III)

The electrochemical oxidation-reduction of the system titanium(IV) — titanium(III) is slow at dropping mercury electrode in perchloric acid or hydrochloric acid, but becomes rapid in the presence of thiocyanate ions.On the basis of polarization curves, interpreted according to a preliminary theoretical study, the authors conclude that the rapid electrochemical reaction is the following: TiOH.SCN⁺² + H⁺ + e ? TiSCN⁺² + H₂OAn application of the findings to the polarographic determination of titanium is given.     

Séparation et dosage de traces de sodium contenues dans des sels de potassium

Résumé Pour séparer et doser les traces de sodium dans les sels de potassium, l'auteur fait appel à deux techniques relativement récentes: la chromatographie sur échangeurs d'ions, la photométrie de flamme.La chromatographie permet de se trouver dans des conditions idéales pour la photométrie de flamme (un seul cation, un seul anion).Il est possible, en s'entourant de précautions indispensables, de doser 0,001% de sodium à ± 10%, grâce à la sensibilité de la photométrie de flamme, et ceci, malgré l'extrême simplicité de l'appareil utilisé.

---

Summary To separate and determine traces of sodium in potassium salts, the author used two relatively recent techniques: chromatography on ion exchangers, and flame photometry.The chromatography made it possible to discover ideal conditions for the flame photometry (a single cation, one anion).It is possible, by providing certain indispensable precautions, to determine 0.001% of sodium within ± 10%, thanks to the sensitivity of the flame photometry, and even so, despite the extreme simplicity of the apparatus required.

---

Zusammenfassung Zur Trennung und Bestimmung von Natriumspuren in Kaliumsalzen werden die Ionenaustauschchromatographie und die Flammenphotometrie verwendet. Die Chromatographie ermöglicht die Einhaltung der für die Flammenphotometrie bestgeeigneten Bedingungen: je ein Kation und ein Anion. Bei Beachtung der angegebenen Arbeitsvorschriften läßt sich dank der Empfindlichkeit der Flammenphotometrie trotz größter Einfachheit der verwendeten Geräte 0,001% Natrium mit einer Genauigkeit von ±10% bestimmen.

     

Étude de la photolyse de sels de sulfonium,photoamorceurs cationiques

Arylonium salts allowed the development of cationic photopolymerization. A number of reports about the photolysis of triarylsulfonium salts can now be found in the literature. These works deal with salt photofragmentation kinetics, the visualization of the photolysis process by real time pH mesurements and with the acid photoliberation kinetics by potentiometric titrations.     

Contribution à l'étude des méthodes de dosages électrotitrimétriques

The author establishes a general equation for the polarisation curve of an oxidation-reduction system taking into account the kinetics of reactions and concentration polarisation, and shows how it can be applied to the interpretation of titration curves obtained by the dead-stop end-point method of Foulk and Bawden and by the derivative method of Reilley, Cooke and Furman.     

Utilisation de l'acide phénylarsonique en turbidimétrie: Dosage du tantale

A turbidimetric method is described for the determination of tantalum with phenylarsonic acid. The method is fast and rarely requires preliminary separation. The only interfering elements are zirconium and niobium when present in molar ratios greater than Nb : Ta = 1 and Zr : Ta = 5.