Question

why should a magnesium ribbon be cleaned before burning in air

Answer 1

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

Answer 2

A new magnesium ribbon covered with layer of copper,if we try to burn alike it won't burn easily,so it recommend to clean with sandpaper before the Experiment.

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