2. Solved Papers
  3. NEET

NEET AIPMT SOLVED PAPER SCREENING 2007

  • question_answer
                    A steady current of 1.5 A flows through a copper voltameter for 10 min. If the electrochemical equivalent of copper is \[30\times {{10}^{-5}}g\,{{C}^{-1}}\] the mass of copper deposited on the electrode will be:                   

    A)                  0.40 g                  

    B)                  0.50 g  

    C)                  0.67 g 

    D)                  0.27 g

    Correct Answer: D

    Solution :

                    Key Idea: Apply first law of electrolysis during deposition of charge on an electrode through electrolysis.                 If m is the mass of a substance deposited or liberated at an electrode during electrolysis when a charge q passes through electrolyte, then according to Faraday's first law of electrolysis.                 \[m\,\propto \,\,q\]                 \[orm=zq\]                 where z is a constant of proportionality and is called electrochemical equivalent (ECE) of the substance.                 If an electric current \[I\] flows through the electrolyte, then                 q = lt                 \[\therefore m=zit\]                 Here, mass of copper deposited on the electrode                 \[m=30\times {{10}^{-5}}\times 1.5\times 10\times 60\]                 \[=27\times {{10}^{-2}}=0.27\,g\]


You need to login to perform this action.
You will be redirected in 3 sec spinner