Figure shows an electrolyte of AgCl through which a current is passed. It is observed that 2.68 g of silver is deposited in 10 minutes on the cathode. Find the heat developed in the 20Ω resistor during this period. Atomic weight of silver is 107.9 g mol–1.


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Given:
Mass of silver deposited, m = 2.68 g



Time, t = 10 minutes = 600 s


Using the formula, from faraday’s law of electrolysis –



where,


m = the mass of the substance deposited on the electrode


z=electrochemical equivalence


i=current passing


t=time taken






Now, heat developed in the 20 Ω resistor from Joule’s heating effect,



Where


I is the current in the circuit


R is the resistance of the resistor


T is the time period for which the current is allowed to flow through the circuit


Putting the above values in the formula, we get





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