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प्रश्न
Paheli kept some water in a beaker for heating. She observed that tiny bubbles appeared before the water started to boil. She boiled the water for about 5 minutes and filled it in a bottle up to the brim and kept the bottle air tight till it cooled down to room temperature.
Why did the tiny bubbles appeared?
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उत्तर
The tiny bubbles appeared when the water started boiling because of the air dissolved in water. When she started boiling the water, the air that was dissolved in the water escaped in the form of bubbles.
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संबंधित प्रश्न
Match the statements in Column A, with those in Column B.
| Column A | Column B |
| 1. Largest Constituent of air, which dilutes the activity of oxygen. |
(a) Oxygen |
| 2. A gas used for filling weather observation balloons. | (b) carbon acid |
| 3. An acid formed by the dissolution of sulphur dioxide gas in water. | (c) Sulphur acid |
| 4. An acid formed by the dissolution of carbon dioxide in water. | (d) Helium |
| 5. A gas vital for respiration. | (e) Nitrogen |
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