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Question
Higher order Thinking question
Boiling of water is a physical change; but boiling of egg is a chemical change. Why?
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Solution
- Boiling of water is a physical change:
On boiling, water is converted into steam. If we cover the beaker with a lid, steam condenses back to water. So, boiling, of water is a physical change since only the physical state of water changes.
- Boiling of egg is chemical change:
When egg is boiled, chemical nature of the egg changes. The properties of a boiled egg are totally different from the raw egg. Hence, boiling of an egg is a chemical change.
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