During the purification of copper by electrolysis:
(a)the anode used is made of copper ore
(b)pure copper is deposited on the cathode
(c)the impurities such as Ag, Au present in solution as ions
(d)concentration of `CuSO_4` solution remains constant during dissolution of Cu

Options

A. the anode used is made of copper ore
B. pure copper is deposited on the cathode
C. the impurities such as Ag, Au present in solution as ions
D. concentration of `CuSO_4` solution remains constant during dissolution of Cu

Answer

To solve the question regarding the purification of copper by electrolysis, let's analyze each statement step by step:

### Step 1: Analyze the Anode Material
- **Statement (a)**: The anode used is made of copper ore.
- **Explanation**: In the electrolysis process for copper purification, the anode is typically made of impure copper, not copper ore. The impure copper dissolves, releasing copper ions into the solution.
- **Conclusion**: This statement is **false**.

### Step 2: Analyze the Cathode Process
- **Statement (b)**: Pure copper is deposited on the cathode.
- **Explanation**: During electrolysis, copper ions from the solution gain electrons at the cathode and are deposited as pure copper metal. This is the primary goal of the electrolysis process.
- **Conclusion**: This statement is **true**.

### Step 3: Analyze the Impurities
- **Statement (c)**: The impurities such as Ag, Au present in solution as ions.
- **Explanation**: While silver (Ag) and gold (Au) may be present in the anode, they do not remain in solution as ions during the electrolysis process. Instead, they are deposited as solid impurities (anode mud) below the anode.
- **Conclusion**: This statement is **false**.

### Step 4: Analyze the Concentration of CuSO4
- **Statement (d)**: The concentration of CuSO4 solution remains constant during dissolution of Cu.
- **Explanation**: As copper dissolves from the anode, copper ions enter the solution, and an equal amount of copper ions is deposited at the cathode. Therefore, the overall concentration of CuSO4 remains constant throughout the process.
- **Conclusion**: This statement is **true**.

### Final Summary of Statements:
- (a) False
- (b) True
- (c) False
- (d) True

### Conclusion:
The true statements regarding the purification of copper by electrolysis are (b) and (d).

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