1)why should magnesium ribbon be cleaned before it is burnt in air?2)is this an oxidation-reduction reaction?

Question

if so then what is being oxidised and what is being reduced?
(answer before 9 p.m.on 3rd may2007 please)

Answer 1

A thin film of MgO and Mg3N2 forms on the ribbon while it is kept in storage, this film is inert and decomposes at extremely high temperatures.

When the ribbon is cleaned, this film is removed and the ribbon can now burn easily.

Answer 2

is this some style of filthy euphemism? If confident then I somewhat have, I burnt it to a crisp, scrapped off the carcinogenic layer in to the bin, burnt lower back and lined in lard and gooseberry jam earlier ingesting it total, purely to regurgitate it and proportion with my companion. That’s this style of close relation we've. Or have a I misunderstood the question? I do desire no longer, that would desire to be embarrassing.