Identify the reagents shown in bold in the following equations as nucleophiles or electrophiles:

HO— acts as nucleophile because it is an electron rich species  always ready to donate their electron pair to electron deficient species.

Here   —CN acts as a nucleophile because it id electron rich species and it can donate electron pair to electron deficient species.

CH3CO+  acts  as an electrophile as it is an electron deficient species. Always ready to accept the electron pair from electron rich species.