Question

why should a magnesium ribbon be cleaned before burning in air

Answer 1

Answer: Magnesium ribbon must becleaned before burning in air so that the layer of magnesium oxide (which is formed due to reaction of magnesium with air) can be removed in order to get the desired chemical reaction.

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Answer 2

Magnesium ribbon has magnesium oxide on its outer layer due to corrosion. MgO has moisture in it , which slows down the ignition process . So magnesium ribbon must be cleaned before burning it

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