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Question
Give the reason why the following is considered as chemical changes.
An iron nail kept open in the atmosphere rusts.
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Solution
Rust of iron is a chemical change as iron rust [Fe2O3χ H20] is a brown flaky powder having a different composition from original iron metal, which is an irreversible change.
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RELATED QUESTIONS
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Rusting of iron is a chemical change.
Match the columns.
| Column A | Column B |
| 1. a change which cannot be easily reversed | a. man-made change |
| 2 a change that repeats itself at regular intervals | b. chemical chang |
| 3. a change that is made by humans | c. physical change |
| 4. a change in which the original substance cannot be obtained | d. periodic change |
| 5. a change where no new substance is formed | e. irreversible change |
| f . slow change |
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- Substance retains its identity.
- The change is permanent.
- No new substance is formed.
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