CDS · 2026 Science & Technology › Physics & ChemistryConsider the following statements : 1. The temporary hardness in water is due to the presence of bicarbonates of calcium. 2. The permanent hardness in water is due to the presence of soluble chlorides and sulphates of calcium and magnesium. 3. The permanent hardness in water is removed by adding Na₂CO₃ to water. Which of the statements given above are correct ?
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