What is the role of a catalyst in gel formulations?

• A. A substance that slows the reaction
• B. A substance that is consumed in the reaction
• C. A chemical which speeds up the reaction and reduces setting time
• D. A filler material

Answer: (C)

In gel formulations, curing is a chemical process that builds the gel network, and a catalyst is used to speed up that reaction. The catalyst provides or activates the initiation step that starts polymerization, so the gel sets more quickly when activated (for example by light in UV/LED systems). This makes the setting time shorter and the application more efficient. The other ideas don’t fit the role: a substance that slows the reaction would defeat the purpose of curing quickly, a filler adds bulk rather than changing reaction speed, and being consumed isn’t the defining function of a catalyst in this context—the emphasis is on accelerating the reaction to achieve faster setting.