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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is not a free radical, but it is a reactive oxygen species?
assistant
The correct answer is  Most powerful oxygen free radical is Hydroxyradical.
Least powerful Reactive Oxygen species(ROS) is Hydrogen peroxide.
Precursor of all Reactive Oxygen species is Superoxide radical.
H2O2 is not a free radical,  but a ROS.

Reference- Review of biochemistry Pg-411