Classify the reaction: N2 (g) + 3H2 (g) à 2NH3 (g)

For the reaction N2 (g) + 3H2 (g) 2NH3 (g),

we have two reactants combining to form a single product. This type of reaction is called a Synthesis reaction.

(Quick side note) : Because this is a reversible, you could write it in the opposite direction as a decomposition reaction.