Permanent hardness of water is due to the presence of

Options

A. Sulphates of Mg and Ca
B. Bicarbonates of mg and Ca
C. Sulphates of Na and K
D. Bicarbonates of Na and K

Answer

**Step-by-Step Solution:**

1. **Understanding Hardness of Water:**
- Water hardness is primarily caused by the presence of certain minerals. There are two types of hardness: temporary and permanent.

2. **Identifying Temporary Hardness:**
- Temporary hardness is mainly due to the presence of soluble bicarbonates of calcium and magnesium. These bicarbonates can be removed by boiling the water, which converts them into insoluble carbonates that precipitate out.

3. **Identifying Permanent Hardness:**
- Permanent hardness, on the other hand, is caused by the presence of sulfates and chlorides of calcium and magnesium. Unlike temporary hardness, these minerals do not precipitate out upon boiling.

4. **Conclusion:**
- Therefore, the permanent hardness of water is due to the presence of sulfates and chlorides of calcium and magnesium.

5. **Final Answer:**
- The correct answer is: Permanent hardness of water is due to the presence of sulfates and chlorides of calcium and magnesium.

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