Question

What is the time required for depositing all the silver present in 125ml of 1m agno3 solution by passing a current of 241.25a?

Answer 1

Answer: Time required for depositing all the silver present in 125ml of 1m agno3 solution by passing a current of 241.25a =50 seconds

Explanation:

• Applying Faraday's first law which states that mass of the substance (m) deposited or liberated at any electrode is directly proportional to the quantity of electricity or charge (Q) passed.
• First, we have to find out mass of Ag+ given

          Using formula:-

Mass of solute = Volume of solution in Litre x Molar mass of solute x Molarity

              Volume of solution = 125 ml = 0.125 L

              Molar mass of Ag+ ion ( solute) = 107.9 g/ mol

              Molarity is given as = 1 M

• Substituting values in formula:-

                       Mass of Ag+ = 0.125 L x 107.9 mol/ L x 1 M

                                             = 13.5 g

• According to faraday's law:-

       1 mole(107.9g) of Ag+ deposited as Ag on electrode require 96487 Coulomb of charge

     Then, 1 g of Ag deposited by = 96487 C / 107.9 g  of charge

     And  13.5 g of Ag deposited by = (96487 C / 107.9 g) x 13.5 g

                                                          = 12072.05 C of charge

• Now, charge = current x time

                   Time = charge/ current

                            = 12072.05/241.25 s

                            = 50 s