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प्रश्न
Bubbles are seen in the test tube during the preparation of lime water.
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उत्तर
Lime water is a saturated solution of calcium hydroxide (Ca(OH)2). It is commonly prepared by passing carbon dioxide gas through a solution containing quicklime (CaO) or slaked lime (Ca(OH)₂) in water.
- Formation of Lime Water: \[\ce{CaO + H2O -> Ca(OH)2}\]
Quicklime reacts with water to form slaked lime (calcium hydroxide), which dissolves slightly in water to form lime water. - Bubbling of CO₂ (Observation of Bubbles): \[\ce{Ca(OH)2 + CO2 -> CaCO3 ↓ + H2O}\]
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When CO₂ gas is passed through the lime water, it reacts with the calcium hydroxide.
- The bubbles observed are CO₂ gas bubbles.
- The reaction produces calcium carbonate, which causes the solution to turn milky.
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संबंधित प्रश्न
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