Question

why should a magnesium ribbon be clean before burning in air​

Answer 1

Explanation:

Magnesium ribbon should be cleaned with sandpaper before burning in the air. ... To remove the Magnesium oxide layer from the ribbon which may prevent or slow down the burning of magnesium ribbon. Unwanted impurities deposited on the magnesium ribbon can be removed and only pure magnesium can be used for the reaction.

Answer 2

Answer:

A magnesium ribbon should be clean before burning in air because magnesium is a highly reactive metal and it can be reacts with oxygen to form a white layer of magnesium oxide and this layer will not burn.