When acetyl chloride reacts with sodium acetate, it undergoes a nucleophilic substitution reaction. The reaction can be represented as follows:

CH3COCl + CH3COONa → CH3COOCH3 + NaCl

In this reaction, the nucleophile is the acetate ion (CH3COO-), which attacks the electrophilic carbon atom of the acetyl chloride molecule. The reaction proceeds via a substitution mechanism, in which the acetate ion displaces the chloride ion from the acetyl chloride molecule. The product of the reaction is ethyl acetate (CH3COOCH3) and sodium chloride (NaCl).