When connected to a silver voltameter, the potential difference across the terminals of a battery having an emf of 12 V and an internal resistance of 2 drops to 10 V . Determine the amount of silver deposited at the cathode in half an hour. The atomic weight of silver is 107.9 g mol ⁻¹ .

Step-by-step solution

The terminal potential difference of the battery is given by V = E - Ir . Substituting the given values, 10 = 12 - I(2) . 2I = 2 I = 1 A . The time for which the current flows is t = 30 min = 1800 s . The total charge passed through the voltameter is Q = It = 1 1800 = 1800 C . According to Faraday's first law of electrolysis, the mass of silver deposited is m = ZQ , where Z is the electrochemical equivalent. Z = Atomic weight Valency F = 107.9 1 96500 g C ⁻¹ . m = 107.9 96500 1800 = 107.9 18 965 2.01 g . The amount