The two reactants combine to form a single product, ammonia, nh3, which is not shown. write a balanced chemical equation for the reaction. based on the equation and the contents of the left (reactants) box how many molecules should be shown in the right (products) box?

If the product is ammonia, the reactants must be the diatomic gases N₂ and H₂. The complete balanced reaction is shown below:

N₂ + 3 H₂ → 2 NH₃

Now, the number of molecules on the left or reactant side are: 2 molecules of nitrogen and 3*3 = 6 molecules of hydrogen. The total number would be 8 molecules. The same number of molecules is counted on the right or product side. This is to obey the Law of Conservation of Mass.