Alkaline Mercuric-Potassium Iodide

Alkaline Mercuric Potassium Iodide TS (Nessler s Reagent) See Mercuric Potassium Iodide TS, Alkaline. 

Nessler s Reagent See Alkaline Mercuric-Potassium. Iodide TS. 

Algin, 24, 54,312, 351 Alginates Assay, 768 Algin Derivative, 331 AlginicAcid, 19 Alkaline Borate Buffer, 848 Alkaline Cupric Citrate TS, 851 Alkaline Cupric Tartrate TS, 849 Alkaline Mercuric-Potassium Iodide TS, 850... 

USE In anal, chemistry for preparation of Nessler s Reagent (alkaline mercuric potassium iodide solution). 

Mercuric-Potassium Iodide TS, Alkaline (Nessler s Reagent) Dissolve 10 g of potassium iodide (KI) in 10 mL of water, and add slowly, with stirring, a saturated solution of mercuric chloride until a slight red precipitate remains undissolved. To this mixture add an ice-cold solution of 30 g of potassium hydroxide (KOH) in 60 mL of water, then add 1 mL more of the saturated solution of mercuric chloride. Dilute with water to 200 mL. Allow the precipitate to settle, and draw off the clear liquid. A 2-mL portion of this reagent, when added to 100 mL of a 1 300,000 solution... 

No turbidity with alkaline mercuric chloride—potassium iodide reagent USP test. 

AMMONIA CONTENT. The concentration of ammonia nitrogen in the water-extractable components of the fabric was determined colorimetrically by Nesslers reaction (23). Under alkaline conditions, Nesslers reagent (mercuric iodide-potassium iodide solution) reacts with ammonia that has been released from ammonium salts by the alkali present to produce a yellow compound by the following reaction ... 

Mercury Derivatives.—The mode of preparation of these compounds is similar to that adopted for the preceding compounds. When mercuric chloride is used and the operations are carried out in methyl alcohol, a yellow powder results, which is soluble in methyl alcohol, glycerine, ethylene glycol, and acidified potassium iodide solution. It is decomposed by water or sodiunr hydroxide aird is only slightly soluble in dilute acids, but if treated with antimony compounds, antimonyl derivatives are obtained, which are more soluble and are stable in alkaline solutions. The decomposition by water is said to give rise to colloidal mercury and 3-amino-4-hydroxyplienylarsenoxide, OH.CgHa.(NH2).AsO. If an excess of mercuric chloride is used, the oxidation proceeds to o-aminophenol, mercurous chloride, and arsenious... 

The pharmacopoeia reagent is a relatively weak solution prepared of potassium iodide R and mercuric iodide R which is further diluted immediately before use. In this it is different from the reagent described in classical Nessler s reagent, which is a saturated filtered solution. The final reagent is a alkaline solution of potassium tetraiodomercurate(II), K2[Hgl4]. 

Mercuric acetylide has never been employed in any practical explosive applicatimi. It has, however, found some use in analytical work because formatitai of the precipitate of mercuric acetylide (from an alkaline solution of mercuric iodide and potassium iodide) can be used for the quantitative determination of acetylene [1]. 

The reaction of ammonia or ammonium compounds with an alkaline solution of mercuric and potassium iodides to give a yellow colour. This reaction can be used to estimate urea, when used in conjunction with the enzyme urease which converts urea to ammonia. 

Urease-Nesslerization methods. The ammonia formed by the urease reaction reacts with mercuric and potassium iodides in alkaline solution to give a yellow colour. However, this method has several disadvantages which has led to its gradual disuse. The major disadvantages are that ... 

Dissolve about 0 5 g in 50 ml of water. For mercuric oxide, add 1 g of sodium chloride and neutralise with 0 1 N hydrochloric acid to methyl orange, thus forming the neutral salt HgCl2,2NaCl. 1 ml 0 1N = 0 01083 g HgO. For mercuric cyanide, add an excess (3 g) of potassium iodide, which forms unionised Hgl2,2KI and liberates an equivalent of ionised KCN. Titrate the alkalinity of the potassium cyanide by additional 0 1 N hydrochloric acid to the same indicator. 1 ml 0 1N = 0 01263 g Hg(CN)2. 

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. 

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