Exams › JEE Main › Chemistry

250 mL of a waste solution obtained from the workshop of a goldsmith contains 0.1 M AgNO3 and 0.1 M AuCl. The solution was electrolyzed at 2 V by passing a current of 1 A for 15 minutes. The metal/metals electrodeposited will be : (E°Ag+/Ag = 0.80V, E°Au+/Au = 1.69V)

1. only gold
2. silver and gold in equal mass proportion
3. silver and gold in proportion to their atomic weights
4. only silver

Correct answer: silver and gold in proportion to their atomic weights

Solution

During electrolysis, metals are deposited based on their reduction potentials and the amount of charge passed. Since both silver and gold are present, and their deposition depends on their respective atomic weights and the total charge, they will be deposited in proportion to their atomic weights, leading to the correct option.

Related JEE Main Chemistry questions

• Which of the following sequences lists the given metals in decreasing order of their standard electrode potentials: Mg, K, Ba and Ca?
• During electrolysis of an aqueous solution of dipotassium succinate, which gas is evolved at the electrodes?
• Which expression gives the equivalent conductance at infinite dilution of Al2(SO4)3, if 9b°Al3+ and 9b°SO4^2− denote the equivalent conductances at infinite dilution of the corresponding ions?
• A weak monobasic acid has an equivalent conductance of 8.0 mho cm^2 for an M/32 solution, while its limiting equivalent conductance at infinite dilution is 400 mho cm^2. What is the dissociation constant of the acid?
• The standard emf of a Daniell cell is 1.10 V. What is the greatest amount of electrical work that can be extracted from this cell?
• During the recharging of a lead storage battery, which reaction takes place at the cathode?

⚔️ Practice JEE Main Chemistry free + battle 1v1 →