<u>Answer:</u> The unbalanced chemical equations are written below.
<u>Explanation:</u>
An unbalanced chemical equation is defined as the equation in which total number of individual atoms on the reactant side is not equal to the total number of individual atoms on the product side. These equations does not follow law of conservation of mass.
The chemical equation for the reaction of nitrogen gas and oxygen gas follows:
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The product formed is nitrogen dioxide.
The chemical equation for the decomposition of dinitrogen pentaoxide follows:
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The product formed is dinitrogen tetroxide and oxygen gas.
The chemical equation for the reaction of ozone to oxygen gas follows:

The product formed is oxygen gas.
The chemical equation for the reaction of chlorine and sodium iodide follows:

The product formed is sodium chloride and iodine gas
The chemical equation for the reaction of magnesium and oxygen gas follows:
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The product formed is magnesium oxide