Question

why should a magnisium ribbon be cleaned before burning in the air

Answer 1

magnesium ribbon shold be cleaned before burning in air due to formation of white layer of magnesium oxide on its surface which hinders the burning of magnesium.

Answer 2

♤ When Magnesium ribbon is exposed in the atmosphere it form a layer of magnesium oxide on its surface.

♤ This layer of magnesium oxide is stable compound to prevent further reaction of magnesium with oxygen.

♤ Hence, it should be cleaned before burning in air to remove this layer so that the metal can be exposed to air properly.