Which electrode (anode or cathode) is designated as positive in an electrolytic cell?
anode****
cathode
both
neither
The electrodes in both Electrolytic and Galvanic Cells are defined by the chemistry that occurs at a given electrode. The anode is always the site of oxidation and the cathode is the site of reduction. In electrolytic cells, the electrodes are connected to a power source because the chemistry of the electrolytic process is not spontaneous. The electrode connected to the positive terminal of the power source is positive in an electrolytic cell and drives the oxidation of negative ions attracted to that electrode. The electrode attached to the negative terminal of the power source is negative in an electrolytic cell and reduces positive ions attracted to that electrode. In Galvanic Cells the chemistry is spontaneous and the charges on the electrodes are a result of oxidation and reduction reactions occurring in a closed circuit. The anode and cathode are paired reactions (see a reduction potential table) that spontaneously undergo oxidation and reduction when coupled in a special configuration called a Voltaic Cell. The anodic reaction (as in the electrolytic cell) is the site of oxidation but unlike the electrolytic process, the anodic material undergoes oxidation and delivers a cation into solution leaving the anode with a surplus of electrons and hence a negative charge. The cathode in the galvanic cell is positive because cations in solution migrate (attracted) to the electrode and remove electrons from that terminal resulting in reduction of that cation and formation of the basic neutral element that typically leaves the system as a ppt, weak electrolyte or gas decomp. product of the reaction. Hope this helps. Good luck ...
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In an electrolytic cell, the anode is designated as positive.
In an electrolytic cell, the anode is designated as positive. To understand why, let's delve into the basics of an electrolytic cell.
An electrolytic cell is a type of electrochemical cell that uses an external power source (such as a battery) to drive a non-spontaneous chemical reaction. This is achieved by applying an electric current through the cell, causing a redistribution of electrons.
Now, let's break down the components of an electrolytic cell. It consists of two electrodes submerged in an electrolyte solution. The electrode connected to the positive terminal of the power source is called the anode, and the electrode connected to the negative terminal is called the cathode.
When the external power source is connected, the anode becomes positively charged, while the cathode becomes negatively charged. This happens because the power source drives electrons from the anode to the cathode through the external circuit.
Now, in an electrolytic cell, positive ions from the electrolyte are attracted to the negative cathode, where they gain electrons and become neutral. Conversely, negative ions are attracted to the positive anode, where they lose electrons and become neutral.
Therefore, in this process, the anode is designated as positive because it attracts negative ions (or anions) due to its positive charge. In contrast, the cathode is designated as negative because it attracts positive ions (or cations) due to its negative charge.
To summarize, in an electrolytic cell, the anode is designated as positive due to its role in attracting negative ions.