Question

why should a magnesium ribbon be cleaned before burning in air? ​

Answer 1

Answer:

call the layer of magnesium oxide can be removed to get the desired chemical reaction

Answer 2

Explanation

Magnesium is very reactive metal. When stored it reacts with oxygen to form a layer magnesium oxide is quite stable and prevents further reaction of magnesium with oxygen. The magnesium ribbon is cleaned by sand paper to remove this layer so that the underlying metal can be exposed into air.

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