Question

why should a magnesium ribbon be cleaned with sand paper before burning ​

Answer 1

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

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.

Hope it helps !