Mercuric nitrate standardization

Mercurous Sulfate. Mercurous s Ai2LX.e[7783-36-0] Hg2S04, is a colodess-to-shghfly-yellowish compound, sensitive to light and slightly soluble ia water (0.05 g/100 g H2O). It is more soluble ia dilute acids. The compound is prepared by precipitation from acidified mercurous nitrate solution and dilute sulfuric acid. The precipitate is washed with dilute sulfuric acid until nitrate-free. Its most important use is as a component of Clark and Weston types of standard cells. 

Elemental composition Be 11.28%, Cl 88.72%. Beryllium may be analyzed in aqueous solution or in solid form by different instrumental techniques (see Beryllium). Chloride may be measured in aqueous solution (after appropriate dilution) by titration with a standard solution of silver nitrate or mercuric nitrate or by ion chromatography or a selective chloride ion electrode. 

Elemental composition Cs 78.94%, Cl 21.06%. An aqueous solution may be analyzed for the element Cs by atomic absorption or emission spectroscopy and chloride by ion chromatography, chloride ion-selective electrode, or by titration with a standard solution of sdver nitrate or mercuric nitrate. 

Elemental composition Fe34.43%, Cl 65.57%. The compound may he identified by x-ray methods. Iron may be analyzed by various instrumental techniques (See Iron). Chloride in the aqueous solution of the compound may be measured by titrating with a standard solution of sdver nitrate or mercuric nitrate or by ion chromatography. 

Elemental composition Ph 74.50%, Cl 25.49%. Lead chloride may be identified by its physical properties and using x-ray analysis. An aqueous solution may he analyzed for lead hy AA, ICP and other instrumental techniques, and for chloride ion hy ion chromatography, or hy titration with a standard solution of silver nitrate or mercuric nitrate. 

An aqueous solution of the compound may be analyzed for Mn by AA, ICP, or other instrumental techniques, and for chloride by ion chromatography or titration against a standard solution of silver or mercuric nitrate. 

A short report (K2) has appeared in which an automatic titrator has been used in a modified version of the Schales and Schales procedure (S2). In the modified method which employs 3 ml of a 1 10 blood filtrate, the standard mercuric nitrate in nitric acid is used as a titrant. The recovery values reported are sufficiently accurate for clinical use ... 

Standard Preparation Transfer 1.71 g of mercuric nitrate [Hg(N03) H20] into a 1000-mL volumetric flask, dissolve in a mixture of 100 mL of water and 2 mL of nitric acid, dilute to volume with water, and mix. Discard after 1 month. Transfer 10.0 mL of this solution into a second 1000-mL volumetric flask, acidify with 5 mL of a 1 5 sulfuric acid solution, dilute... 

Mercuric Nitrate, 0.1 M [32.46 g Hg(N03)2 per 1000 mL] Dissolve about 35 g of mercuric nitrate [Hg(N03)2-H20] in a mixture of 5 mL of nitric acid and 500 mL of water, and dilute with water to 1000 mL. Standardize the solution as follows Transfer an accurately measured volume of about 20 mL of the solution into an Erlenmeyer flask, and add 2 mL of nitric acid and 2 mL of Ferric Ammonium Sulfate TS. Cool to below 20°, and titrate with 0.1 N Ammonium Thiocyanate to the first appearance of a permanent brown color. Calculate the molarity. 

The automated system is controlled by a specially designed programmer which controls the potentiostat, the recorder, two peristaltic pumps, and five solenoid-operated valves which alternately circulate a mercuric nitrate solution, a seawater sample, or a standard solution through the electrode assemblage. Automated analyses for copper, zinc, cadmium, and lead were made on the pier of the Scripps Institution of Oceanography, San Diego, Calif., and aboard ship in Puget Sound, Wash. This report describes the automated system, discusses the performance of the electrode imder continued use, and presents the results obtained in the field. 

To standardize the mercuric nitrate, pipette 10 ml of O.lN potassium chloride into a 250-ml Erlenmeyer flask then add 40 ml of water (measured with a graduate) and 3 drops of 10 per cent sodium nitroprusside. Titrate with mercuric nitrate, shaking well between additions as the end point is neared. The end point is marked by a permanent white turbidity and is quite sharp. When the mercuric nitrate has been standardized, titrate the hexamminecobaltic chloride solution by the same procedure, taking care to have the volume of solution in the titration flask the same as in the standardization. The end point arrives somewhat early because of the reaction HgCh + Hg++—> 2HgCl+ but by performing the standardization and titration under similar conditions, with the final mercuric chloride concentrations almost the same, this error, which is small in any case, becomes quite negligible. 

Standard Test Method for Mercurous Nitrate Test for Copper and Copper Alloys Standard Specification for Cellulosic Fiber (Wood-Base) Loose-Fill Thermal Insulation Standard Test Method for Half-CeU Potentials of Uncoated Reinforcing Steel in Concrete Standard Test Method for Detection of Copper Corrosion from Petroleum Products by the Copper Strip Tarnish Test... 

The chlorine content of the polymer can then be calculated from the consumption of standard mercuric nitrate solution. Modifications to the method are described for overcoming interferences by any sulfur, phosphorus or fluorine present in the polymer. 

Weigh out an amount of sample corresponding to 1.0 to 2.0 mg of chlorine and decompose it in an oxygen flask containing 5.0 ml of water. Wash the stopper and sample holder with 10.0 ml of water, add 0.1 ml of bromophenol blue indicator solution and neutralise the solution with 0.1 N sodium hydroxide to the blue colour of the indicator. Add 0.75 ml of thorium nitrate solution, 0.5 ml of diphenylcarbazone indicator solution and 100 ml of ethanol and titrate the stirred solution with standard mercuric nitrate solution to the appearance of a permanent violet colour. 

To 90 ml of a suitable concentration of mercury in neutral or acetic acid solution add 5 0 ml of N nitric acid from a pipette, mix thoroughly, add 3 0 ml of /)-dimethylaminobenzylidine-rhodanine reagent (0 04 g shaken with 200 ml of ethanol, left overnight and filtered), adjust the volume to 100 ml and mix. Compare with standards prepared by adding suitable known amounts of standard mercuric nitrate solution (0-5 g mercury in 5 ml of concentrated nitric acid, dilute, boil to remove nitrous fumes and dilute to 250 ml make further dilutions so that 1 ml 0 0001 g Hg) to similar amounts of nitric acid and reagents as used in the test solution. Develop the colour in both test solution and standards simultaneously, allow to stand for five minutes and compare. 

For the determination of iodine, one mode of flnish consists of titration with standardized mercuric nitrate solution, with diphenylcarbazone as the indicator ... 

Chlorine at the percentage level at which it occurs in sea water is usually determined by classical procedures using standard silver nitrate as the titrant and potassium chromate indicator, or alternatively by the mercuric thiocyanate procedure using dithizone as indicator. As large dilutions of the original sample are involved in these analyses, it is essential to use grade A glassware and take all other suitable precautions, such as temperature control. 

Soliman and Belal investigated argentimetric (67,68) and mercurimetric (69) methods. Hydralazine precipitates silver from ammoniacal silver nitrate solution. The silver is dissolved with hot nitric acid and titrated with ammonium thiocyanate solution. Alternatively, mercury is precipitated from alkaline potassium mercuric iodide solution. The precipitated mercury is dissolved by adding excess standard iodine solution. The excess iodine is back-titrated with sodium thiosulfate solution after acidifying with acetic acid. 

The sample is titrated with standardized silver nitrate (0.0141 M) in a continuously mixed beaker with an Ag electrode, an Ag/ AgCl electrode, or a chloride—ISE. The reference can be a glass mercuric sulfate, calomel, or Ag/ AgCl electrode. 

Issa et al. [9] used various metal ions for the volumetric determination of mefenamic acid. Mefenamic acid was precipitated from its neutral alcoholic solution by a standard solution of either silver nitrate, mercurous acetate, or potassium aluminum sulfate. In the argentimetric procedure, residual Ag(I) was titrated with standard NH4SCN. With Hg(OAc)2 or potash alum, the residual metal was determined by adding EDTA and conducting back titration of excess of EDTA with standard Pb(N03)2 using xylenol orange indicator. The applied methods were used for the determination in bulk drug substance, and in its formulations. 

Elemental analysis of duplicate samples of econazole nitrate was performed using a Perkin-Elmer 2400 CBN analyser. Approximately 3-mg quantities of material were combusted and measured against an acetanilide standard. The chlorine determination was based on oxygen flask combustion followed by titration against mercuric perchlorate which had been standardized against sodium chloride and chlorobenzoic acid. The oxygen content of the samples was calculated by difference. 

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