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From the solution containing copper (+2...

From the solution containing copper `(+2)` and zinc `(+2)` ions copper can be selectively precipitate using sodium sulphide.

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To selectively precipitate copper ions from a solution containing both copper (Cu²⁺) and zinc (Zn²⁺) ions using sodium sulfide (Na₂S), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding the Ion Composition**: - The solution contains copper ions (Cu²⁺) and zinc ions (Zn²⁺). Both are cations, but they belong to different groups in qualitative analysis. 2. **Identifying the Group of Cations**: - Copper (Cu²⁺) is classified as a group II cation, while zinc (Zn²⁺) is classified as a group III cation. This classification helps in understanding how to selectively precipitate them. 3. **Using Sodium Sulfide**: - Sodium sulfide (Na₂S) is the reagent used for precipitation. When added to the solution, it dissociates into sodium ions (Na⁺) and sulfide ions (S²⁻). 4. **Precipitation Reaction**: - The sulfide ions (S²⁻) react with copper ions (Cu²⁺) to form copper(II) sulfide (CuS), which is a black precipitate: \[ \text{Cu}^{2+} + \text{S}^{2-} \rightarrow \text{CuS (s)} \] - Zinc ions (Zn²⁺) also react with sulfide ions to form zinc sulfide (ZnS), which is a white precipitate: \[ \text{Zn}^{2+} + \text{S}^{2-} \rightarrow \text{ZnS (s)} \] 5. **Comparing Solubility Products (Ksp)**: - The key to selectively precipitating copper over zinc lies in the solubility products (Ksp) of their sulfides. The Ksp of CuS is much lower than that of ZnS, meaning CuS is less soluble and will precipitate first when sodium sulfide is added. 6. **Conclusion**: - Since CuS precipitates before ZnS due to its lower Ksp, we can conclude that copper can be selectively precipitated from the solution using sodium sulfide. Therefore, the statement is true. ### Final Answer: The statement that copper can be selectively precipitated from a solution containing copper and zinc ions using sodium sulfide is **True**. ---

To selectively precipitate copper ions from a solution containing both copper (Cu²⁺) and zinc (Zn²⁺) ions using sodium sulfide (Na₂S), we can follow these steps: ### Step-by-Step Solution: 1. **Understanding the Ion Composition**: - The solution contains copper ions (Cu²⁺) and zinc ions (Zn²⁺). Both are cations, but they belong to different groups in qualitative analysis. 2. **Identifying the Group of Cations**: ...
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