Platinum -bridged

Simultaneous thermal exposure of a sample at various temperatures is provided by the so-called gradient furnace, i.e. a furnace with an approximately linear temperature distribution within the required range. A rod-shaped sample in a platinum boat, or glass fragments on a platinum bridge 10—15 cm in length are placed in the furnace. The method is less accurate but significantly more rapid. 

Kissel-Osterrieder R, Behrendt F, WamatzJ, Metka U, Volpp HR, Wolfram J Experimental and theoretical investigation of the CO-oxidation on platinum bridging the pressure and the materials gap, Proc Combust Inst 28 1341-1348, 2000. 

An oxygen-stabilized rhenium-platinum-bridging carbene has reportedly been synthesized from a mononuclear rhenium carbene. ... 

PtCl2, and platiaum tetrachloride [37773-49-2]. Platiaum dichloride exists in an a- and P-form, the latter containing a Pt core and edge-bridging chlorides. Platinum trichloride [25909-39-1], PtCl, contains Pt(II) and Pt(IV) centers. Other haHdes include two bromides, PtBr2 [13455-12-4] and PtBr ... 

Platinum has many uses in dentistry. Pure platinum foil serves as the matrix in the constmction of fused-porcelain restorations. Platinum foil may be laminated with gold foil for cold-welded foil restorations. Platinum wire has found use as retention posts and pins in crown and bridge restorations. Heating elements and thermocouples in high-fusing porcelain furnaces are usually made of platinum or its alloys (see Platinum-GROUP metals). 

A voltaic cell using this reaction is similar to the Zn-Cu2+ cell the Zn Zn2+ half-cell and the salt bridge are the same. Because no metal is involved in the cathode half-reaction, an inert electrode that conducts an electric current is used. Frequently, the cathode is made of platinum (Figure 18.3, p. 484). In the cathode, Co3+ ions are provided by a solution of Co(N03)3. The half-reactions occurring in the cell are... 

Follow die directions for Question 7 for a salt bridge cell in which die anode is a platinum rod immersed in an aqueous solution of sodium iodide containing solid iodine crystals. The cathode is another platinum rod immersed in an aqueous solution of sodium bromide with bromine liquid. 

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. 

Apparatus. Use the apparatus of Section 14.7. The generator anode is of pure silver foil (3 cm x 3 cm) the cathode in the isolated compartment is a platinum foil (3 cm x 3 cm) bent into a half-cylinder. For the potentiometric end point detection, use a short length of silver wire as the indicator electrode the electrical connection to the saturated calomel reference electrode is made by means of an agar-potassium nitrate bridge. 

Prepare an approximately 0.1 M silver nitrate solution. Place 0.1169 g of dry sodium chloride in the beaker, add 100 mL of water, and stir until dissolved. Use a silver wire electrode (or a silver-plated platinum wire), and a silver-silver chloride or a saturated calomel reference electrode separated from the solution by a potassium nitrate-agar bridge (see below). Titrate the sodium chloride solution with the silver nitrate solution following the general procedure described in Experiment 1 it is important to have efficient stirring and to wait long enough after each addition of titrant for the e.m.f. to become steady. Continue the titration 5 mL beyond the end point. Determine the end point and thence the molarity of the silver nitrate solution. 

A bolometer is essentially a thin blackened platinum strip in an evacuated glass vessel with a window transparent to the infrared rays it is connected as one arm of a Wheatstone bridge, and any radiation absorbed raises the temperature of the strip and changes its resistance. Two identical elements are usually placed in the opposite arms of a bridge one of the elements is in the path of the infrared beam and the other compensates for variations in ambient temperature. Both the above receptors give a very small direct current, which may be amplified by special methods to drive a recorder. 

The platinum complex is square planar, while the palladium dimer also has planar 4-coordination (for other examples of mercaptide bridges see section 3.8.3) [116]. 

Binuclear platinum(III) methyls have been made, these complexes utilizing carboxylate bridges (Figure 3.97b)... 

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