Q1. Why should a Magnesium Ribbon be cleaned before burning in air?
Answer: when magnesium ribbon is exposed into the air for a period of time, it forms a protective layer of Magnesium oxide or Basic Magnesium Carbonate. This layer stops the burning of Magnesium Ribbon. That’s why Magnesium ribbon should be cleaned before burning
Magnesium oxide – MgO
Basic Magnesium carbonate = MgCO3 . Mg(OH)2