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प्रश्न
What do you observe when :
an iron nail is kept in tap water for few days
उत्तर
We observe reddish brown coating on the nail called rust (entirely new substance) is chemical change.
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संबंधित प्रश्न
Name three biochemical catalysts found in the human body.
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NaCI + `AgNO_3` `→`
Fill in the blank
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Precipitate
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