How would you confirm that a colourless liquid given to you is pure water? - Science

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How would you confirm that a colourless liquid given to you is pure water?

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Solution

Every liquid has a characteristic boiling point. Pure water has a boiling point of 100°C (373 K) at 1 atmospheric pressure. If the given colourless liquid boils at even slightly above or below 100°C, then the given liquid is not pure water. It must boil at sharp 100°C. Thus, by observing the boiling point, we can confirm whether a given colourless liquid is pure water or not.

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Chapter 2: Is Matter around us Pure - Exercises [Page 29]

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NCERT Science Class 9
Chapter 2 Is Matter around us Pure
Exercises | Q 6 | Page 29

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