Question

Show the formula of reactants : magnesium oxide with sodium chloride to produce magnesium chloride and sodium oxide

Answer 1

The equation is:
MgO + 2 NaCl = MgCl2 + Na2O
although I doubt very much that reaction actually happens.

Answer 2

is there really such a reaction?

Answer 3

I guess whit oxygen it will react

Answer 4

I doubt it. All four of those things are very stable. It would take some pretty extreme conditions to make anything happen, and even then it seems unlikely.