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Question
How would you show that setting of curd is a chemical change?
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Solution 1
Once the curd is formed, milk cannot be re-obtained from it. Also, both milk and curd have different properties. Since these are the properties of a chemical change, the setting of curd is a chemical change.
Solution 2
- When curd sets, its chemical composition changes.
- Curd is obtained as a new substance.
- Curd cannot be obtained again in its original state (milk).
- The chemical properties change.
- Its taste becomes sour.
Thus, the setting of curd is a chemical change.
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