Modern inorganic chemistry

94 ACIDS AND BASES: OXIDATION AND REDUCTION

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solution

Figure 4.2. The Daniell cell, an example of an electrochemical cell

shown diagrammatically in Figure 4.2. A series of experiments using
different metals and their salts enables an approximate order of
reducing power, or of reactivity, to be established for metals—this
is known as the reactivity or electrochemical series.
Electron transfer can be established experimentally in reactions
involving only ions in solution. Inert electrodes, made from platinum,
are used to transfer electrons to and from the ions. The apparatus
used is shown in Figure 43, the redox reaction being considered

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1

Fe" (aq) Br 2 (aq)

4.3. Apparatus to show electron transfer between ions and solution