Which of the following species acts as an weakest reducing agent?

Step-by-step solution

A reducing agent is oxidized by losing electrons. The standard oxidation potential measures the tendency for oxidation: larger, more positive values indicate stronger reducing agents. For lithium, the oxidation half-reaction is Li Li ⁺ + e ⁻ , with E^ _ ox = +3.04~ V , indicating it is a very strong reducing agent. Lithium ion ( Li ⁺ ) and fluorine ( F ₂ ) are not reducing agents, as Li ⁺ tends to be reduced and F ₂ is a strong oxidizing agent. Fluoride ion ( F ⁻ ) can be oxidized via F ⁻ 1 2 F ₂ + e ⁻ , with E^ _