Platinum chemical properties

Thus it can be seen that elements in and near the island of stabiHty based on element 114 can be predicted to have chemical properties as foUows. Element 114 should be a homologue of lead, that is, should be eka-lead, and element 112 should be eka-mercury, element 110 should be eka-platinum, etc (26,27). If there is an island of stabiHty at element 126, this element and its neighbors should have chemical properties like those of the actinide and lanthanide elements (26). 

Physical and Mechanical Properties. Whereas there are some similarities in the physical and chemical properties between corresponding members of the PGM triads, eg, platinum and palladium, the PGMs taken as a unit exhibit a wide range of properties (2). Some of the most important are summarized in Table 2. 

Many complexes and coordination compounds exist as isomers, compounds that contain the same numbers of the same atoms but in different arrangements. For example, the ions shown in (13a) and (13b) differ only in the positions of the Cl ligands, but they are distinct species, because they have different physical and chemical properties. Isomerism is of more than academic interest for example, anticancer drugs based on complexes of platinum are active only if they are the correct isomer. The complex needs to have a particular shape to interact with DNA molecules. 

Beside these catalytically active metallophosphine dendrimers (see above), preliminary studies on the chemical properties of phoshorus-based dendrimers complexed to metals such as platinum, palladium and rhodium have been described by Majoral, Caminade and Chaudret [21], They showed that these macromolecules (see Scheme 13) could be useful for the (in situ) generation of metallodendrimer catalysts. 

A rich family of intensely blue-coloured, linear platinum complexes, called platinum blues , has received a great body of attention in the years from 1970 to 1990, not only for their unusual physico-chemical properties, but also for their antitumor properties.14... 

Linear polycarbosilanes and polycarbosiloxanes-especially those containing arylene units in the chain-have specific physico-chemical properties which can be applicable in heat-resistant materials [29-31]. Phenylene-silylene-ethylene-polymers, which may serve as potential substrates for applications as membrane materials are usually obtained in the presence of platinum catalysts [32], although other transihon-metal complexes have also been tested in this process. 

Platinum metah—includes unreactive transition elements located in groups 8, 9, and 10 of periods 5 and 6. They have similar chemical properties. They are ruthenium, rhodium, palladium, osmium, iridium, and platinum. 

Platinum is the main metal in the platinum group, which consists of metals in both period 5 and period 6. They are ruthenium (Ru), rhodium (Ro), and palladium (Pd) in period 5 and osmium (Os), iridium (Ir), and platinum (Pt) in period 6. All six of these metals share some of the same physical and chemical properties. Also, the other metals in the group are usually found in platinum ore deposits. 

Elemental composition (anhydrous salt) Pt 47.60%, H 0.49%, Cl 51.90%. The compound may be identified by its physical and chemical properties. Platinum in an aqueous solution of the compound can be analyzed by flame AA or ICP spectroscopy. Also, the compound can be measured by gravimetry following precipitation with ammonium chloride, hydrogen sulfide, or silver nitrate (see Reactions above). 

Trace impurities in noble metal nanoclusters, used for the fabrication of highly oriented arrays on crystalline bacterial surface layers on a substrate for future nanoelectronic applications, can influence the material properties.25 Reliable and sensitive analytical methods are required for fast multi-element determination of trace contaminants in small amounts of high purity platinum or palladium nanoclusters, because the physical, electrical and chemical properties of nanoelectronic arrays (thin layered systems or bulk) can be influenced by impurities due to contamination during device production25 The results of impurities in platinum or palladium nanoclusters measured directly by LA-ICP-MS are compared in Figure 9.5. As a quantification procedure, the isotope dilution technique in solution based calibration was developed as discussed in Chapter 6. 

Feolite catalysts modified by transition metals are interesting and difficult subjects to study. In one of the first studies of zeolites as catalysts, Rabo and co-workers (1) used a zeolite catalyst containing 0.5% platinum for isomerization of n-paraffins. In this reaction the metal-zeolite system acted as a typical representative of the bifunctional catalysts. Studies of zeolites modified by transition metals ( 2, 3, Jf) showed that their polyfunctional properties are determined by the structural and chemical properties of the zeolite and by the state of the metal in it. In this paper we discuss new data on the metal state after reduction as well as the catalytic functions of zeolite catalysts containing nickel and platinum. 

The foregoing paragraphs have described platinum on alumina catalysts in a very general way and have also attempted to give a brief discussion of the reason why platinum is so commonly used as a reforming catalyst. In the following sections, the physical and chemical properties of platinum-alumina catalysts will be discussed in more detail, since this information will be of considerable help in understanding the way in which these catalysts function. 

Electrodes of this sort have many different chemical properties from pure mercury electrodes, because of the formation of a gold or platinum amalgam [18]. Normally, a drop is suspended just prior to an experiment, so this problem will be of no serious consequence. Nevertheless, since the solubility of these noble metals in mercury is about 0.05 M at room temperature [19], the concentration of gold or platinum in mercury may be quite significant on a longer time scale. In such cases, gold or platinum may form intermetallic compounds with several metals that are electrodeposited into the mercury [18]. 

In laboratory animals, parenteral administration of organic and inorganic selenium (210 to 12,000 ig/kg) has been shown to protect against cisplatin-induced nephrotoxicity. Protection occurs without apparent inhibition of the antineoplastic activity of cisplatin, although this may be attributed to the fact that selenium administration allows for higher doses of cisplatin to be used. Additionally, selenium administration reduces cisplatin-induced myelosuppression. This raises a concern similar to that with administering cisplatin with thiol compounds, i.e., that the reduction of myelosuppression may indicate that selenium can also interfere with the antitumor activity of cisplatin. Selenium, with chemical properties similar to those of sulfur, can bind with platinum and... 

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