Nucleophilicity follows the same rules as Electronegativity? True/False
False, Within a group in the periodic table, increasing polarisation of the nucleophile as you go down a group enhances the ability to form the new C-X bond and increases the nucleophilicity, so I- > Br- > Cl- > F-. The electron density of larger atoms is more readily distorted i.e. polarised, since the electrons are further from the nucleus.