What is a catalyst?

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternative pathway for the reaction that has a lower activation energy, making it easier for the reactants to transform into products. In the context of nail technology, catalysts can be particularly relevant in curing processes, such as those used in gel nails, where a catalyst can speed up the polymerization process, allowing technicians to achieve faster results.

The other options represent concepts that do not define a catalyst. A solvent, for instance, is a substance that dissolves a solute, while the creation of polymers involves a different set of chemical variables that may or may not include catalysts. Lastly, the elimination of pathogens refers to disinfection practices, which are also unrelated to the definition of a catalyst.