Silver reduction potential

Hunn, B. D. Baughman. M. L. Silver, S. C. et al. (1986). Technical Potential for Electrical Energy Conservation and Peak Demand Reduction in Texas Buildings. Austin, TX Center for Energy Studies, University of Texas. Interlaboratoiy Working Group. (1997). Scenarios of U.S. Carbon Reductions Potential Impacts of Energy-Efficient... 

The silver reductor has a relatively low reduction potential (the Ag/AgCl electrode potential in 1M hydrochloric acid is 0.2245 volt), and consequently it is not able to effect many of the reductions which can be made with amalgamated zinc. The silver reductor is preferably used with hydrochloric acid solutions, and this is frequently an advantage. The various reductions which can be effected with the silver and the amalgamated zinc reductors are summarised in Table 10.11. ... 

Reductant equivalent weights of, 847 Reduction 409 by chromium(II) salts, 409 by hydrogen sulphide, 416 by Jones reductor (zinc amalgam), 410 by liquid amalgams, 412 by silver reductor, 414 by sulphurous acid, 416 by tin(II) chloride, 415 by titanium(II[), 410 by vanadium(II), 410 see also Iron(III), reduction of Reduction potentials 66 Reference electrodes potentials, (T) 554 Relative atomic masses (T) 819 Relative error 134 mean deviation, 134... 

Reduction always occurs at the cathode. Note that H°ed for silver is +0.7991 volt, according to the Table of Standard Reduction Potentials. E°ed for copper is +0.337. This means that the copper metal is higher in the activity series than the silver metal, so copper metal will reduce the silver ion. The equation that describes reduction (or the cathode reaction) is therefore... 

When two interval scales are used to measure the amount of change in the same property, the proportionality of differences is preserved from one scale to the other. For example. Table 1.4 shows reduction potentials of three electrochemical half-cell reactions measured in volts with reference to the standard hydrogen electrode (SHE, E°) and in millivolts with reference to the standard silver-silver chloride electrode (Ag/AgCl, ). For the SHE potentials the proportion of differences between the intervals +0.54 to +0.80 and +0.34 to +0.80 is... 

One more example demonstrates how to use standard reduction potentials to determine the standard potential of a cell. Let s say you wanted to construct a cell using silver and zinc. This cell resembles the Daniell cell of the previous example except that a silver electrode is substituted for the copper electrode and a silver nitrate solution is used in place of copper sulfate. From Table 14.2, it is determined that when silver and copper interact silver is reduced and copper oxidized. The two relevant reactions are... 

The formal reduction potential of silver ion in DMF was found to be +0.579 0.004 V vs. SCE. The values of the stability constants of the DMF complexes of silver(I) in various solvents are given in Table 38. It was observed that the complexes were most stable in nitroethane.274... 

The specific value of the crossover depends on both the emulsion used and the conditions of exposure. For exposures made in air, the crossover occurs at a reduction potential that is less negative the lower the pAg.of the emulsion (248). Honda and associates (264) attribute this dependence to "anodic and cathodic shifts of the band edge of the silver halide, respectively." They support this explanation by experiments on the effects of silver ions and halide ions on the sensitized photocurrent in an electrochemical cell having an AgBr or AgCl sheet crystal window. 

Although direct excited-state electron transfer from 2PA dyes to monomer is successful for polymerizing acrylates and depositing silver, few other materials can be patterned in the same way for effective initiation, the reduction potential for the monomer, V2(M/M- ), needs to be greater, i.e. less negative, than the excited-state oxidation potential for the initiator, E /2(M+/M ), which can be estimated from... 

In order to get a clearer picture of conditions existing on deposition of metals, let us discuss some examples. The deposition potential of silver from a normal solution of its salt almost equals the standard reduction potential tca = + 0.8 V, and the potential of hydrogen evolved from a neutral solution Ttn, equals 0.059 log 10-7 = —0.41 V. Both potentials are so wide apart that not even the polarization occurring at higher current densities can considerably affect the relative position of both curves. For this reason, silver will be deposited from the solution prior to hydrogen until practically all Ag+ ions will be... 

Remember, silver is one of the four metals that only have one charge. If you forget the charge, it does appear on the reduction potentials chart. Also note that the spectator ions are omitted. 

Answer Again, notice the single element as a reactant and a solution of an ionic compound as the other reactant. These are clues for a replacement. You should check to make sure that magnesium is capable of replacing silver in solution. A quick glance at the reduction potentials indicates that it will easily replace silver, so the reaction should be completed ... 

Answer To solve the problem we need to know the values for n and E. Let s begin by looking at E. Zinc is the anode in this reaction, and silver is the cathode. You can tell this in two ways the first is that the reduction potential for silver is more positive than zinc, and second because silver is being reduced in the reaction. Knowing this, we can use Equation 18.2 to determine E ... 

The correct answer is (C). You can answer this by looking at the table of standard reduction potentials. Silver is the only substance that is below copper. 

The correct answer is (A). In a voltaic cell, the substance with the most positive reduction potential will be the cathode. Ag+ has a value of 0.80 V, and Ni2+ has a value of -0.25 V. That would make the silver electrode the cathode. In a voltaic cell, the cathode always has a positive charge. 

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