Question

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

Answer 1

HEYA!!
----------

➡A magnesium ribbon should be cleaned with a Sand paper before burning it in air . This is because Magnesium has a later of OXIDE on its surface . This oxide hinders its burning .

➡so this oxide later is removed by cleaning magnesium ribbon with a Sand paper.

➡Burning of Magnesium :-

2Mg + O2-------------2MgO.

➡Magnesium burns with a dazzling white flame and gets finally reduced to a powdery substance that is magnesium oxide which resembles table salt .

----------------------------------------------------------------------------------------------------
--------------------------------------------------------⭐⭐⭐

Answer 2

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