California Registered Dental Assistant (RDA) Written Practice Exam

The primary active agent in the solution used for unsaturated chemical vapor sterilization is?

1. Alcohol

2. Ethylene oxide

3. Formaldehyde

4. Hydrogen peroxide

The correct answer is: Formaldehyde

Formaldehyde is the primary active agent in the solution used for unsaturated chemical vapor sterilization because it has strong antimicrobial properties. Alcohol (choice A) is not typically used for sterilization because it evaporates too quickly and does not effectively kill the necessary microorganisms. Ethylene oxide (choice B) is a commonly used sterilization method, but it is generally used for materials that are sensitive to heat and moisture, such as plastic or rubber. Hydrogen peroxide (choice D) is a disinfectant, but it is not typically used for sterilization. It may be used in some sterilization processes as a secondary agent to enhance the effectiveness of other sterilizing agents, but it is not the primary active agent in unsaturated chemical vapor sterilization.