Chemistry · No topic
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If an electrophile is the attacking reagent, which one is the most reactive?
- A
R-I
- B
R-F
- C
R-Br
- D
R-Cl
The correct answer is R-F (Option B). Fluorine is the most reactive halogen because of its high electronegativity and the strong polarization it can induce in the carbon bonded to it. This makes R-F a very strong electrophile, capable of attracting nucleophiles effectively. In contrast, R-I (Option A) is less reactive than R-F, despite iodine being a large atom, due to weaker bond strengths. R-Br (Option C) is more reactive than R-Cl (Option D), but both are still less reactive than R-F. Overall, the reactivity order for these electrophiles is R-F > R-Br > R-Cl > R-I.
R-I represents an alkyl iodide. While iodine is a larger atom and has weaker bonds, making it a good leaving group, it is not the most reactive electrophile compared to fluorine.
R-F represents an alkyl fluoride. Fluorine is highly electronegative and forms a strong bond, but it is also a very reactive electrophile due to its ability to stabilize positive charges effectively.
R-Br indicates an alkyl bromide. Bromine is a decent leaving group and is more reactive than chlorine or iodine, but not as reactive as fluorine.
R-Cl denotes an alkyl chloride. Chlorine is less reactive than bromine and fluorine as an electrophile due to its lower electronegativity and bond strength.
Tagged under Chemistry · No topic · 2025