Q12 of 37 Page 1

A. Calculate the mass of Ag deposited at cathode when a current of 2 amperes was passed through a solution of AgNO3 for 15 minutes.

(Given Molar mass of Ag = 108g mol–1 1F = 96500 C mol–1)


B. Define fuel cell.

(A) Given : current = 2 amperes


Time = 15 mins = 900 seconds


Molar mass of Ag = 108g/mol


1F = 96500 C/mol


We know that charge = current time


= 2A 900sec = 1800C


Now, Ag+ + e-→ Ag


So, 1F is needed to deposit 1 mole of Ag


This means 96500 C is needed to deposit 108g of Ag ( given above )


We have 1800C of charge, and it will deposit g of Ag


= 2.014 g


(B) A fuel cell is defined as the galvanic cell that is designed to convert the energy of combustion of fuels like hydrogen,


methane, methanol, etc. directly into electrical energy.


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