The significance of the minus sign is that the battery in Fig. 10.8 must supply a voltage in excess of 1.23 V in the indicated sense in order to decompose water into hydrogen and oxygen, both at atmospheric pressure. The overall cell reaction is obtained by summing the anodic and cathodic half-cell reactions shown in Fig. 10.8:

In the anode compartment, water decomposes into: i) oxygen gas, which bubbles off and is collected; ii) hydrogen ions, which migrate towards the cathode in the bridge separating the two compartments; iii) electrons, which enter the external circuit to supply the cathodic reaction. At the cathode, the hydrogen ions and the electrons produced in the anode are combined to produce hydrogen gas.

Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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