Question

which of the choices is a weakest nucleophile in a polar protic solvent? a) fb) ic) brd) cle) all of these

Answer 1

Fluoride (F-) is the weakest nucleophile in polar protic solvents due to its small size and high electronegativity, which leads to strong solvation and reduced nucleophilicity.

Step-by-step explanation:

The question asks which halide ion is the weakest nucleophile in a polar protic solvent. In such a solvent, nucleophilicity generally follows the trend of basicity, which is inversely related to the size and electronegativity of the halide ions. Iodide (I-), being the largest and least electronegative of the halides mentioned, would tend to be the strongest nucleophile. Fluoride (F-), on the other hand, is the smallest and most electronegative halide; it is more tightly solvated in polar protic solvents due to its high charge density and hydrogen bonding capabilities, making it less available for nucleophilic attack. Therefore, fluoride (F-) is the weakest nucleophile in a polar protic solvent among the options given.

Answer 2

In a polar protic solvent, fluoride (F-) is the weakest nucleophile because it is the most tightly solvated halide, making it less available to participate in nucleophilic reactions.

Step-by-step explanation:

In a polar protic solvent, the weakest nucleophile among the halides listed (F-, I-, Br-, Cl-) is fluoride anion (F-). In polar protic solvents, the reactivity of nucleophiles is closely related to their ability to solvate and the solvents' ability to stabilize the anions through hydrogen bonding.

Fluoride is the smallest halide and is tightly solvated by the solvent molecules, which makes it less available for nucleophilic attack.