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What is the colour of the precipitate obtained by passing CO ₂ gas through lime water?

Options

  1. AGreen
  2. BBlue
  3. CWhite
  4. DBrown

Correct answer

C. White

Step-by-step solution

Carbon dioxide reacts with limewater (a solution of calcium hydroxide, Ca ( OH )₂ ), to form a white precipitate (appears milky) of calcium carbonate, CaCO ₃ . Adding more carbon dioxide results in the precipitate dissolving to form a colourless solution of calcium hydrogen carbonate.

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