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प्रश्न
The quantity of charge required to obtain one mole of aluminium from Al2O3 is ______.
विकल्प
1F
6F
3F
2F
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उत्तर
The quantity of charge required to obtain one mole of aluminium from Al2O3 is 3F.
Explanation:
\[\ce{AI2O3 -> 2AI^{3+} + 3O^{2-}}\]
\[\ce{AI^{3-} + 3^{e-} -> AI}\] .....(For mole)
3F charge is required to obtain 1 mole Al from Al2O3.
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संबंधित प्रश्न
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Oxidation-reduction reactions are commonly known as redox reactions. They involve transfer of electrons from one species to another. In a spontaneous reaction, energy is released which can be used to do useful work. The reaction is split into two half-reactions. Two different containers are used and a wire is used to drive the electrons from one side to the other and a Voltaic/Galvanic cell is created. It is an electrochemical cell that uses spontaneous redox reactions to generate electricity. A salt bridge also connects to the half-cells. The reading of the voltmeter gives the cell voltage or cell potential or electromotive force. If \[\ce{E^0_{cell}}\] is positive the reaction is spontaneous and if it is negative the reaction is non-spontaneous and is referred to as electrolytic cell. Electrolysis refers to the decomposition of a substance by an electric current. One mole of electric charge when passed through a cell will discharge half a mole of a divalent metal ion such as Cu2+. This was first formulated by Faraday in the form of laws of electrolysis.
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