Which process involves adding a chemical to change the composition of an odor?

The process that effectively involves adding a chemical to change the composition of an odor is neutralization. This technique works by introducing a specific agent that chemically reacts with odor-causing substances, thereby altering them to mitigate or eliminate the odor. For instance, neutralization could involve adding a base to a strong acidic odor, resulting in a reaction that reduces the odor's potency.

Oxidation is a process where a substance loses electrons or increases its oxidation state, which can also help reduce odors but not necessarily by changing the composition of the odor in the way neutralization does. Absorption entails trapping odor molecules in a medium, which may reduce their presence but does not directly change their chemical structure. Pairing, while it may refer to combining substances in other contexts, does not specifically address altering odor composition in the same definitive manner as neutralization.