Potassium platinum chloride

F. Platinichloride reagent [27 ml M potassium iodide -f 5 ml of 5% potassium platinum chloride (K2PtCl5)+ 100 ml water]... 

In biological materials, various nonspecific precipitants have been used in the gravimetric deterrnination of choline, including potassium triiodide, platinum chloride, gold chloride, and phosphotungstic acid (28). Choline may also be determined spectrophotometricaHy and by microbiological, enzymatic, and physiological assay methods. 

Reagent 1 Spray solution 1 Treat 1 ml of a platinum chloride solution (S <7o) wi 1.5 g potassium iodide and mix with 3 ml cone, hydrochloric add at 11 ml water. 

Compounds Ammonium chloroplatinate sodium chloroplatinate platinic chloride platinum chloride sodium tetrachloroplatinate potassium tetrachloroplatinate ammonium tetrachloroplatinate sodium hexachloroplati-nate potassium hexachloroplatinate ammonium hexachloroplatinate... 

But [said he] it was still necessary to learn the base of the salt. Its solution could not be precipitated either by tartaric acid in excess or by platinum chloride. Consequently it could not be potassium. I mixed another portion of a solution of the same salt with a few drops of pure potash, but without its becoming cloudy. Therefore it contained no more magnesia hence it must be a salt with soda for a base. I calculated the quantity of soda which would be necessary to form it but it always resulted in an excess of about 5 parts in 100 of the mineral analyzed. Therefore, since it seemed probable to me that the different substances might not have been well washed, Or that the analysis might not have been made with sufficient precision in other respects, I repeated it twice more with all the care possible, but always with results very little different. I obtained. Silica. 78 45, 79.85, Alumina 17 20, 17.30 Sulfate 19.50, 17.75. At last, having studied this sulfate more closely, I soon found that it contained a definite fixed alkali, whose nature had not previously been known (21). 

The electrical conductivity.—E. Klein10 showed that if there is a difference between the conductivity of a mixture of salts in soln. and the mean conductivities of the separate constituents, a double salt is probably formed. The molecular conductivity of a salt, and if possible of its components at different dilutions, has been employed to determine the number of component ions in a soln. it was used, for example, by A. Werner (1893-1901) with the cobalt, chromium, platinum, and other ammines.11 In moderately cone. soln. the double salts are but little ionized, and the difference between the conductivities of eq. soln. of potassium zinc chloride, ZnCl2.2KCl, and of the sum of the constituents amounts to nearly 36 per cent., a value which is greatly in excess of that whieh would be due to the mutual influence of salts with a common ion. Tables of the molecular conductivities of salts show that with very few exceptions, at a dilution of 1024 litres and 25°, most salts have conductivities approximating those indicated in Table XIX. 

The production of such substances as white lead, lead sulphate, oxides, hydroxides, and sulphides of the heavy metals, can be effected by the electrolysis of a suitable solution, such as sodium (or potassium) nitrate, chloride, or sulphate, with an attackable anode and a cathode of platinum or some metal not attacked by the electrolyte. 

Representative Chemicals c/s-Dichlorodiammine platinum (cisplatin) c/s-Platinum chloride Potassium chloropaletinite... 

Potassium iodide gives a tost for platinum which is very delicate. When added to a solution of platinum chloride a color appears which varies from rose red to brown or black Ptl, may be precipitated. An excess of KI produces K2PtI , brown, sparingly soluble. Iron, eo (( . r, and oxidizing agents interfere with this test. 

Characters and Tests.—Colourless, rhomhoidal crystalline plates, cool saline taste, sparingly soluble in cold water. Its aqueous solution is not affected by silver nitrate or ammonium oxalate. Strongly heated, it fuses, gives off oxygen gas, and leaves a white residue (potassium chloride), which readily dissolves in water, and produces a solution which yields a white precipitate (silver chloride) with silver nitrate, indicating the presence of chlorine, and a yellow precipitate (potassium-platinic chloride) with platinum chloride, showing the presence of potassium. It explodes when triturated in a mortar with sulphur. ... 

The developed plates ate thoroughly dried, and the spots detected by spraying with a chloro-platinic reagent comprising 1 ml of 0.2% platinum chloride soln., O.I ml 20% potassium iodide soln., 0.1 ml of 3-4% hydrochloric acid and 20 ml of acetone. It is convenient to combine the prepared soln. of platinum chloride, hydrochloric acid and acetone and to add the potassium iodide soln. just before spraying these two soln. stored in a... 

In 1829 a crystalline substance was isolated by refluxing platinum(IV) chloride in ethanol and then adding potassium chloride. This compound, Zeise s salt, was analyzed as KCl—PtCl2C2H4. Upon thermal decomposition, some ethylene was liberated. Hydrolysis gave acetaldehyde. Because of the liberation of ethylene and the oxidative hydrolysis to acetaldehyde, it was suspected that ethylene was somehow incorporated into this apparent platinum chloride salt. Many tentative structures were proposed, for instance [5-29] and [5-30]. 

Method A. Cool a solution of the nitrate-free dichloride, prepared from or equivalent to 5 0 g. of palladium or platinum, in 50 ml. of water and 5 ml. of concentrated hydrochloric acid in a freezing mixture, and treat it with 50 ml. of formahn (40 per cent, formaldehyde) and 11 g. of the carrier (charcoal or asbestos). Stir the mixture mechanically and add a solution of 50 g. of potassium hydroxide in 50 ml. of water, keeping the temperature below 5°. When the addition is complete, raise the temperature to 60° for 15 minutes. Wash the catalyst thoroughly by decantation with water and finally with dilute acetic acid, collect on a suction filter, and wash with hot water until free from chloride or alkali. Dry at 100° and store in a desiccator. 

Color. Many water samples have a yellow to brownish-yeUow color which is caused by natural substances, eg, leaves, bark, humus, and peat material. Turbidity in a sample can make the measurement of color uncertain and is usually removed by centrifiigation prior to analysis. The color is usually measured by comparison of the sample with known concentrations of colored solutions. A platinum—cobalt solution is used as the standard, and the unit of color is that produced by 1 mg/L platinum as chloroplatinate ion. The standard is prepared from potassium chloroplatinate (K PtCl ) and cobalt chloride (C0CI26H2O). The sample may also be compared to suitably caUbrated special glass color disks. 

Bromine and bromides can be detected quaUtatively by a number of methods. In higher concentrations bromine forms colored solutions in solvents such as carbon tetrachloride [56-23-5] and carbon disulfide [75-15-0]. Bromine reacts with yeUow disodium fluorescein [518-47-8] to form red disodium tetrabromofluorescein (eosin) [548-26-5] C2QH Br4Na20. As Httle as 0.3 p.g of bromide can be detected and chlorides do not interfere (56). Bromine reacts with platinum sulfate [7446-29-9] Pt(S0 2> solution to form red to brown crystals of potassium hexabromoplatinate [16920-93-7] K PtBr ( )-... 

Aqueous hydrofluoric acid can be freed from lead by adding ImL of 10% strontium chloride per KXhnL of acid, lead being co-precipitated as lead fluoride with the strontium fluoride. If the hydrofluoric acid is decanted from the precipitate and the process repeated, the final lead content in the acid is less than 0.003 ppm. Similarly, lead can be precipitated from a nearly saturated sodium carbonate solution by adding 10% strontium chloride dropwise (l-2mL per lOOmL) followed by filtration. (If the sodium carbonate is required as a solid, the solution can be evaporated to dryness in a platinum dish.) Removal of lead from potassium chloride uses precipitation as lead sulfide by bubbling H2S, followed, after filtration, by evaporation and recrystallisation of the potassium chloride. 

Apparatus. Use the apparatus shown in Figs. 14.2(a) and (b). The generator cathode (isolated auxiliary electrode) consists of platinum foil (4 cm x 2.5 cm, bent into a half cylinder) and the generator anode (working electrode) is a rectangular platinum foil (4 cm x 2.5 cm). For potentiometric end point detection, use a platinum-foil electrode 1.25 cm x 1.25 cm (or a silver-rod electrode) in combination with an S.C.E. connected to the cell by a potassium chloride- or potassium nitrate-agar bridge. 

To set up a saturated calomel electrode, a saturated solution of potassium chloride is first prepared from pure potassium chloride and de-ionised water, and this is then shaken for some hours with analytical grade mercury(I) chloride so that the solution is also saturated with this substance. Pure mercury is placed in the electrode vessel to a depth of about 1 cm the platinum contact must be... 

This electrode is perhaps next in importance to the calomel electrode as a reference electrode. It consists of a silver wire or a silver-plated platinum wire, coated electrolytically with a thin layer of silver chloride, dipping into a potassium chloride solution of known concentration which is saturated with silver chloride this is achieved by the addition of two or three drops of 0.1M silver nitrate solution. Saturated potassium chloride solution is most commonly employed in the electrode, but 1M or 0.1 M solutions can equally well be used as explained in Section 15.1, the potential of the electrode is governed by the activity of the chloride ions in the potassium chloride solution. 

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