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Question
Which one of the following is not a chemical change ?
Options
formation of curd
ripening of banana
sublimation of naphthalene
corrosion of photo frame
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Solution
sublimation of naphthalene
Sublimation of naphthalene is not a chemical change because it only allows naphthalene to change its state from solid to vapour. No new compound is formed and the vapour can again be condensed to solid form.
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