Question

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

Answer 1

Answer :-

Magnesium ribbon must be cleaned before burning in air so that the layer of magnesium oxide (which is formed due to reaction of magnesium with air) can be removed in order to get the desired chemical reaction.

Magnesium ribbon should be cleaned before burning it in air to remove the oxide layer from it which may prevent or slow down the burning of magnesium ribbon.

Answer 2

Hey there!!! ♥️

Magnesium ribbon be cleaned before burning in air because oxide layer is formed on the outer surface of magnesium and it slows down the burning process. That's why we rubbed it by sandpaper before burning.