Question

. In your words describe what an electrolytic cell is (1 mark). When characterizing redox reactions, why do we use standard cell potentials, and what are they standard to? Are standard cell potentials written in terms of oxidation or reduction? (1 mark) Use your lecture notes to state the half-cell reaction equation that requires 0.15 V of electricity to occur (1 mark). Using this reduction half-cell reaction equation answer the following question. How much of the metal, in grams, is deposited onto the electrode if 5.842x10-2 C/s of current passed through the cell for 13 minutes and 5 seconds?

Answer 1

Electrolytic cell :

The cell that make use of electrical energy to carry a chemical reaction is called electrolytic cell.

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It is not possible to calculate electrode potentials but is possible to know cell potential. To know electrode potential, one of the electrodes is taken as reference electrode at standard conditions. this standard electrode is standard hydrogen electrode. At this condition, standard pressure is 1 bar and standard temperature is 298 K.

With help of this we will be able to calculate standard electrode potentials of all other electrodes.

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Standrd electrode potentals are reduction potentials

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reduction potential equal to 0.15 V is for the following half cell reaction, (From tables)

Sn4+ (aq.) + 2 e --------------> Sn2+

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According first law of electrolysis,

W = M c t / Z F

W = 118.71 * 5.842 * 10^-2 * 785 / (2 * 96500)

W = 0.0282 g.