Consider the following statements:<br>1. The temporary hardness in water is due to the presence of bicarbonates of calcium.<br>2. The permanent hardness in water is due to the presence of soluble chlorides and sulphates of calcium and magnesium.<br>3. The permanent hardness in water is removed by adding Na_2CO_3 to water.<br>Which of the statements given above are <strong>CORRECT</strong>?

  1. A. 1 and 2 only
  2. B. 2 and 3 only
  3. C. 1 and 3 only
  4. D. 1, 2 and 3

Correct Answer: D. 1, 2 and 3

Explanation

All three statements are correct. Washing soda (Na_2CO_3) removes permanent hardness by reacting with soluble chlorides and sulphates to form insoluble carbonates.

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