Lead acetate solution

Sodium mlphanilate.—Burns with difficulty, leaving a residue of (chiefly) sodium sulphide. Add dil. HCl, and confirm without delay the evolution of HjS by means of a filter-pa per moistened with lead acetate solution. Typical of salts of the sulphonic acids. Acetone sodium bisulphite.—Almost non-inflammable, leaving a colourless residue of sodium sulphite and sulphate. Transfer residue to a test-tube, add dil. HCl, warm, and confirm the SO2 evolved. 

Sulphur. Moisten the centre of a filter-paper with lead acetate solution. Then add about 10 ml. of dilute hydrochloric acid to the residue in the evaporating-basin, and at once cover the latter with the paper. If zinc sulphide is present in the residue, the hydrogen sulphide evolved will give a definite daA brown coloration with the lead acetate paper. The presence of hydrogen sulphide can often be confirmed by its odour. 

Removal of sulphur as sodium sulphide. Dissolve about 0 i g. of c> stine in a few ml. of 10% NaOH solution. Add a few drops of lead acetate solution and boil for 1 minute. The solution darkens owing to the formation of lead sulphide. 

Sulphur, as sulphide ion, is detected by precipitation as black lead sulphide with lead acetate solution and acetic acid or with sodium plumbite solution (an alkaLine solution of lead acetate). Halogens are detected as the characteristic silver halides by the addition of silver nitrate solution and dilute nitric acid the interfering influence of sulphide and cyanide ions in the latter tests are discussed under the individual elements. 

Prepare a solution of sodium plumbite by adding 10 per cent, sodium hydroxide solution to a few drops of about N lead acetate solution until the white precipitate of lead hydroxide initially formed just redissolves to a clear solution. Add 1 ml. of the fusion solution the presence of sulphiu- is indicated by a black precipitate of lead sulphide. 

Acidify 2 ml. of the fusion solution with dilute acetic acid, and add a few drops of lead acetate solution. A black precipitate of lead sulphide indicates the presence of sulphur. 

PbF2 is readily prepared by the action of hydrogen fluoride on lead hydroxide, lead carbonate, or a-lead oxide. It can also be obtained by precipitation from lead nitrate or lead acetate solutions using potassium fluoride, ammonium fluoride, or ammonium bifluoride. 

Fig. 2 The influence of the reagent concentration on the sensitivity of detection detection of equal amounts of luteolin with basic lead acetate solution that was (A) undiluted, (B) diluted 1 + 4 and (C) diluted 1 + 50.

The tube B is loosely packed with purified glass wool soaked in lead acetate solution (to remove hydrogen sulphide and trap acid spray), and C is a capillary tube (4 mm external and 0.5 mm internal diameter). Place 1.0 mL... 

Thenard A process for making white lead pigment (basic lead carbonate) by boiling litharge (lead monoxide) with lead acetate solution and passing carbon dioxide gas into the suspension. 

Testing for Sulphur.—The qualitative test for sulphur is carried out in the same way as that for nitrogen. Ignite the substance in a small tube with sodium, dissolve the product in water, and add to one half of the cooled solution a few drops of sodium nitroprusside solution freshly prepared by shaking a few particles of the solid salt with cold water. A violet colour indicates the presence of sulphur. Since the nitroprusside reaction is extremely sensitive and does not allow any estimate of the amount of sulphur to be made, filter the second half of the liquid, add lead acetate solution to the filtrate, and acidify with acetic acid. According as the amount of sulphur is small or large, a dark turbidity or a more or less heavy precipitate will form. 

Materials Required Arsenic limit test apparatus HgCl2—paper smooth white filter paper (having thickness in mm of 400 paper = weight in g per Sq. M.), soaked in a saturated solution of HgCl2, pressed to get rid of excess of soln. and dried at about 60°C in the dark lead acetate solution 10.0% w/v soln. of PbAc2 in C02 free water KI (AsT), 1.0 g Zn (AsT) 10.0 g Dilute Arsenic solution (AST) Standard stains, Test Solutions—are prepared according to the Indian Pharmacopoeia 1996. 

In analysing the caffeine of energy drinks, an accurately weighed amount of 15 mL of sample to 50 mL volumetric flask containing 25 mL water. Two milliliters of basic lead acetate solution was added to this solution and diluted the mark with distilled water. After filtering, 25 mL of filtrate was taken and 0.25 g of NaHCOj was added to this solution. Then, the solution was filtered. Five milliliters of filtrate was transferred to a 25 mL volumetric flask and adjusted to volume with distilled water. The peak amplitudes of the first-derivative spectra was measured at 287 and 260 nm. The sample preparation procedure was also used for PLS-1 method and the absorbances of this solution were recorded between 240-320 mn. 

Elemental composition Cd 77.81%, S 22.91%. In crystalline state, it may be identified by x-ray diffraction measurement. In aqueous acid extract following digestion with nitric acid, cadmium may be measured by various instrumental techniques, (see Cadmium). Warming with dilute mineral acids liberates H2S, which may be identified by its odor or by browning of a white paper soaked in lead acetate solution. 

Elemental composition Ca 55.56%, S 44.44%. The compound may be identified from the odor of H2S evolved when mixed with dilute acids. A paper moistened with lead acetate solution and exposed to liberated H2S turns... 

Elemental composition H 5.92%, S 94.08. Hydrogen sulfide may be distinguished by its characteristic odor. The gas turns a paper soaked in lead acetate solution black. Many infrared sensors are commercially available for in-situ measurements of H2S. It may be monitored semiquantitatively by Draeger tubes. It also may be analyzed by GC following trapping over molecular sieves and thermal desorption. Either a flame photometric detector or a sulfur chemiluminescence detector may be used for GC analysis. It may be separated on a capillary column such as Carboxen 1006 PLOT or SPB-1 SULFUR (Supelco Catalog 1999 Supelco Inc., BeUefonte, PA). 

Reaction with hydrogen sulfide forms black precipitate of lead sulfide, PbS. A paper soaked with lead acetate solution turns black on exposure to H2S, a test often used to detect sulfide. 

On the basis of the above observations, a common extraction and cleanup procedure was developed and applied in two recently reported liquid chromatographic methods for the determination of either chlorothiazide and hydrochlorothiazide (558) or chlormethiazide (559) in bovine milk. Both of these methods involve a defatting step by milk centrifugation. Tire defatted milk (4.75 ml) is mixed with 2 ml 5% lead acetate solution and extiacied with 9 ml acetonitrile. Following centrifugation, the supernatant is extracted with 25 ml water-saturated... 

Immerse an iron plate into a test tube containing a lead acetate solution. 

Preparation of Lead by Displacement with Zinc. Pour several millilitres of a lead acetate solution into a test tube and lower a zinc plate into it. What is observed Write the equation of the reaction. In which acids does lead dissolve best of all ... 

Pass a stream of carbon dioxide into the basic lead acetate solution obtained. What is the composition of the precipitate Write the equations of the reactions. 

Wet several strips of filter paper with a lead acetate solution, put them on glass, and let them dry in the air. Introduce the dried paper into the flame of burner. What happens What is lead acetate used for Keep the remaining salt for following experiments. 

Preparation and Properties of Lead(IV) Oxide, a. Prepare a saturated transparent solution of chlorinated lime and a solution of 3 g of lead acetate in 5 ml of water. Add an equal volume of a lead acetate solution heated to 50 °C to the first solution while stirring it. Heat the reaction mixture to 100-110 °C. Wash the precipitate first with water by decantation, and next with a dilute nitric acid solution (what ions are washed off here ). Filter off the product, again wash it two or three times on the funnel with water and dry it at 100 °C. Keep the preparation. Write the equation of the reaction. 

Roast 2-3 g of lead carbonate at 450-500 °C in a porcelain bowl. When decomposition of the salt terminates, roast the substance at the same temperature for another two or three hours. Next transfer the product into a beaker and boil it several times with a lead acetate solution. Pour off the solution from the precipitate, filter off the latter, wash it with hot water, and dry it in a drying cabinet at... 

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