Michigan Esthetician State Board Practice Exam

What term describes atoms or molecules that have unpaired electrons?

1. Free radicals

2. Ions

3. Molecules

4. Cations

The correct answer is: Free radicals

The term that describes atoms or molecules that have unpaired electrons is free radicals. These species are often highly reactive because unpaired electrons seek to pair up, making free radicals eager to interact with other atoms or molecules. This reactivity is significant in various biological and chemical processes, including those related to skin damage and aging. In the context of skin care and esthetics, free radicals can cause oxidative stress, which contributes to the aging process and various skin conditions. Understanding the role of free radicals is essential for estheticians, as they often recommend products high in antioxidants to neutralize these reactive species and protect the skin. The other choices refer to different concepts: ions are charged particles resulting from the loss or gain of electrons, molecules are stable collections of atoms bonded together, and cations specifically refer to positively charged ions. None of these options imply the presence of unpaired electrons, which is a key characteristic of free radicals.