有機 protic and aprotic - 考試

15) Protic and aprotic solvents are very similar as solvents
except fortheir 15) ______

A) dielectric constant.
B) ability to stabilize anions by hydrogen bonding.
C) ability to stabilize cations by hydrogen bonding.
D) polarity.
E) ability to stabilize cations with unshared pairs of electrons.

答案是 b 可是為什麼？ 那c為什麼不行選
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