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प्रश्न
Give the reason why the following is considered as chemical changes.
A bright light is seen evolved when a strip of magnesium is heated.
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उत्तर
Magnesium is heated producing a bright light to form MgO in the air is a chemical change as the composition changes (MgO white powder) is formed, is irreversible. We cannot get magnesium back from MgO.
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