Zinc compared with nickel

Figure31.42 Effect of discharge rate (in terms of C, the nominal hour discharge rate) on energy output Yardney Silvercel rechargeable sllver-zinc battery compared with nickel-cadmium, nickel-lronand lead-acid batteries (Courtesyof Yardney)...

Solid-state, esr spectra of [Cu(Et2dtc)] and [Cu S2P(OPr )2 2] dissolved in coordinating and noncoordinating solvents have been compared with single-crystal and powdered samples diluted with the corresponding complexes of divalent nickel and zinc. With noncoordinating... 

Rodriguez-Torres etal. [235] have used ammonia-containing baths for Zn-Ni alloy electrodeposition on Pt. Zinc and nickel species exist in the form of [Zn(NH3)4] + and [Ni(NH3)6] " complexes in such solutions. The deposition at pH 10 was investigated and compared with deposition from ammonium chloride baths at pH 5. The Ni content in the alloys was found to be 40-60% higher from the ammonia-containing bath than from the acidic baths. The deposition mechanism was found to be affected by complexation of the metal cations by ammonia. 

How do the monoxides of chromium, manganese, iron, cobalt, and nickel compare in basic strength with the oxides of copper and zinc and with the oxides of the alkali and alkaline earth metals How do the sesquioxides, R203, compare with the monoxides of this group as regards basic strength ... 

Zn(OH)2 is soluble in the alkaline solution as [Zn(OH)3]- until the solution is saturated with K[Zn(OH)3]. In addition Zn(OH)2 can be dehydrated to ZnO. An enhanced power density (when compared with the - Leclanche cell) is accomplished by using particulate zinc (flakes) soaked with the alkaline electrolyte solution. This anode cannot be used as a cell vessel like in the Leclanche cell. Instead it is mounted in the core of the cell surrounded by the separator the manganese dioxide cathode is pressed on the inside of the nickel-plated steel can used as battery container. In order to limit self-discharge by corrosion of zinc in early cells mercury was added, which coated the zinc effectively and suppressed hydrogen evolution because of the extremely low exchange current density... 

However, it is a quite striking fourth parameter that oxidizing aqua ions under equal circumstances are more acidic (have lower pK). Thus, iron(III) is distinctly more acidic than aluminium(III) and chromium(III), copper(II) more acidic than nickel(II) and zinc(II), and quite excessive acidity is observed for mercury(II)41), palladium(II)42,81) and thallium(III) aqua ions, compared with the much smaller beryllium(II) and aluminium(III). This tendency takes extreme proportions 841 in gold(III) complexes. 

Yang et al. [53] prepared a novel series of metal-containing poly(imide)s. Polymers of pyromellitic dianhydride with the zinc, strontium, lead, calcium and nickel salts of p-aniline sulfonic acid, were prepared and examined by C CPMAS NMR. There was little difference in the chemical shifts of the dianhydride carbons, compared with the chemical shifts of the poly(imide) with diaminodiphenyl methane. 

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