Answer:
See explanation
Step-by-step explanation:
The word equation is just a statement of the reaction in words as follows;
Magnesium oxide ----> Magnesium metal + oxygen gas
An unbalanced stoichiometric equation doesn't have equal number of atoms of each element on both sides.
Hence the unbalanced stoichiometric equation is as follows;
MgO(s) -----> Mg(s) + O2(g)