nucleophilcity

[milk242]

Hi everyone,

 

I have a pretty simple question on nucleophilicity in a polar protic solvent.

 

Is it true that usually the more stable the charge is, the better the nucleophile is in a protic solvent?

 

If so, why is carboxylate ion a worse nucleophile than ethoxide ion? I thought the resonance stabilized the carboxylate ion to decrease its electron density, thus the protic solvent has less of an effect in shielding it from the electrophile.

 

Thanks in advance