Hardness of water is due to dissolved impurities of

Options

A. calcium and magnesium salt
B. barium and magnesium salts
C. calcium and strontium salts
D. sodium and potasium salts

Answer

To solve the question regarding the hardness of water and the dissolved impurities responsible for it, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Hardness of Water**:
- Hardness of water refers to the presence of certain dissolved minerals that affect its properties, primarily calcium and magnesium salts.

2. **Identifying the Salts**:
- The main contributors to water hardness are the salts of calcium (Ca²⁺) and magnesium (Mg²⁺). These ions can come from various sources, including natural mineral deposits and human activities.

3. **Analyzing the Options**:
- The question provides several options:
- A) Calcium and magnesium salts
- B) Beryllium and magnesium salts
- C) Calcium and strontium salts
- D) Sodium and potassium salts

4. **Evaluating Each Option**:
- **Option A**: Calcium and magnesium salts are known to cause hardness in water.
- **Option B**: Beryllium salts are not typically associated with water hardness.
- **Option C**: While strontium can contribute to hardness, it is not as significant as calcium and magnesium.
- **Option D**: Sodium and potassium salts do not contribute to hardness; they are typically associated with water softness.

5. **Conclusion**:
- Based on the analysis, the correct answer is **Option A: Calcium and magnesium salts**. These are the primary dissolved impurities responsible for the hardness of water.

### Final Answer:
The hardness of water is due to dissolved impurities of **calcium and magnesium salts**.

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