Silver standard reduction potentials

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... 

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... 

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... 

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 corrosion products of noble metals such as copper and silver are complex and affect the use of these metals as decorative materials. Under normal atmospheric conditions copper forms an external layer of greenish copper carbonate called patina. Silver tarnish is silver sulfide (Ag2S), which in thin layers gives the silver surface a richer appearance. Gold, with a positive standard reduction potential (1.50 volts), significantly larger than that for oxygen (1.23 volts), shows no appreciable corrosion in air. 

The standard reduction potential for Ag /Ag is 0.80 V versus NHE. Comparison with the diagram in Fig. 3 shows that the silver ion is not able to oxidize aldehydes except under basic conditions. Yet under such conditions silver oxides are formed and precipitate. 

The value of for the cell was found to be 0.9834 volt at 25 C, and since the standard (reduction) potential of the right-hand i.e., silver chloride, electrode was recorded above as 0.2224 volt, it follows that the standard (oxidation) potential of the zinc electrode is given by + 0.2224 0.9834 volt, so that n is 0.7610 volt at 25 . 

Ahmed A. Mohamed, Alice E. Bruce and Mitchell R. M. Bruce TABLE 1. Standard reduction potentials of gold and silver compounds1... 

Tarnished silver contains Ag2S. The tarnish can be removed by placing silverware in an aluminum pan containing an inert electrolyte solution, such as NaCl. Explain the electrochemical principle for this procedure. [The standard reduction potential for the... 

Based on the standard reduction potentials given above, if a silver electrode and a chromium electrode are connected in a voltaic cell, which electrode will undergo oxidation and which will undergo reduction Explain how you can tell. 

The reaction continues and current passes until all the iodide is used up. At this point some means of endpoint detection is needed. Two methods are commonly adopted. The first uses an amperometric circuit with a small imposed voltage that is insufficient to electrolyze any of the solutes. When the mercury ion concentration suddenly increases, the current will rise because of the increase in the concentration of the conducting species. The second method involves using a suitable indicator electrode. An indicator electrode may be a metal electrode in contact with its own ions or an inert electrode in contact with a redox couple in solution. The signal recorded is potentiometric (a cell voltage vs. a stable reference electrode). For mercury or silver we may use the elemental electrodes, because they are at positive standard reduction potentials to the hydrogen/hydrogen ion couple. 

TABLE 1. Standard reduction potentials of gold and silver compounds ... 

From the values of the standard reduction potentials, we can see that copper is oxidized, and silver is reduced. We then use equation 13.2 to find the cell potential ... 

The high adsorption capacity of Ag+ ions by all the activated carbons was attributed to the reduction of Ag+ ions to metallic silver by the hydroquinone groups present on the carbon surface, which in turn are oxidized to quinone groups. This redox process is supported by the standard reduction potentials of Ag+ (Ag+ + e Ag, E = 0.7996 V) and quinhydrone electrode, = 0.6995 V. The increase in adsorption of Ag+ ions by the ammonia-treated sample was attributed to the formation of silver amino complexes which are quite stable under the conditions used in these studies. 

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