Which of the following sulphate is insoluble in `H_(2)O`

Options

A. `CuSO_(4)`
B. `PbSO_(4)`
C. `CdSO_(4)`
D. `Bi(SO_(4))_(3)`

Answer

To determine which sulfate is insoluble in water among the given options (CuSO4, PbSO4, CdSO4, BiSO4), we can analyze the solubility of each sulfate systematically.

### Step-by-Step Solution:

1. **Identify the sulfates in the options**:
- CuSO4 (Copper(II) sulfate)
- PbSO4 (Lead(II) sulfate)
- CdSO4 (Cadmium sulfate)
- BiSO4 (Bismuth sulfate)

2. **Check the solubility of each sulfate**:
- **CuSO4**: Copper(II) sulfate is known to be soluble in water.
- **PbSO4**: Lead(II) sulfate is generally known to be insoluble in water. The ionic bonds between lead ions (Pb²⁺) and sulfate ions (SO4²⁻) are strong, making it difficult for water molecules to separate them.
- **CdSO4**: Cadmium sulfate is soluble in water due to the favorable interactions between cadmium ions and water molecules.
- **BiSO4**: Bismuth sulfate has moderate solubility in water, but it is not completely insoluble.

3. **Conclusion**: After analyzing the solubility of each sulfate, we find that the only sulfate that is insoluble in water is **PbSO4 (Lead(II) sulfate)**.

### Final Answer:
The sulfate that is insoluble in water is **PbSO4 (Lead(II) sulfate)**.

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