The increasing order of nucleophilicity of the following nucleophiles is;

Step-by-step solution

Anions are more nucleophilic than neutral. So, H 2 O is least nucleophilic. nucleophilicity ∝ e -   density Greater the delocalization of charge, lesser will be nucleophilicity. O H - > C H 3 C O O - > C H 3 S O 3 - > H 2 O