(English Medium) ICSE Class 10 - CISCE Question Bank Solutions for Chemistry

Write two applications of electrolysis in which the anode diminishes in mass.

What ions must be present in a solution used for electroplating a particular metal?

Electroplating steel objects with silver involves a three-step process.

Step 1: A coating of copper is applied to the object.

Step 2: A coating of nickel is applied to the object.

Step 3: The coating of silver is applied to the object.

1. 1. A diagram of the apparatus used for step 1 is shown
      
      
      1. The chemical process taking place on the surface of the object is \[\ce{Cu^2+(aq) + 2e- ->Cu(s)}\]
         What is the observation seen on the surface of the object?
      2. Explain why the concentration of copper ions in the electrolyte remains constant throughout step 1.
2. Give two changes which would be needed in order to coat nickel on to the object in step 2.
3. Write down the reaction taking place at the positive electrode during step 3.