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Permanent hardness of water is due to the presence of

Options

  1. Asulphates of sodium and potassium
  2. Bsulphates of magnesium and calcium
  3. Ccarbonates of sodium and magnesium
  4. Dbicarbonates of magnesium and calcium

Correct answer

B. sulphates of magnesium and calcium

Step-by-step solution

Permanent hardness of water is usually caused by the presence of calcium sulfate and/or magnesium sulfates in the water.

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