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प्रश्न
Which of the following are physical changes ?
- melting of iron metal
- rusting of iron metal
- bending of an iron rod
- drawing a wire of iron metal
पर्याय
(i), (ii) and (iii)
i), (ii) and (iv)
(i), (iii) and (iv)
(ii), (iii) and (iv)
उत्तर
(i), (iii) and (iv)
The process in statement (ii) is a chemical change because rusting causes formation of a new compound. Other statements are examples of physical changes where no new compounds are formed. In the process mentioned in other statements, original form of iron can be obtained back from moulded forms.
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