Acyl halides are rather reactive compounds often synthesized to be used as intermediates in the synthesis of other organic compounds. For example, an acyl halide can react with:
*water, to form a carboxylic acid.  This hydrolysis is the most heavily exploited reaction for acyl halides as it occurs in the industrial synthesis of acetic acid.
*an alcohol to form an ester
*an amine to form an amide
*an aromatic compound, using a Lewis acid catalyst such as AlCl, to form an aromatic ketone. See Friedel-Crafts acylation.
*carboxylic acids to form an organic acid anhydrides.
In the above reactions, HX (hydrogen halide or hydrohalic acid) is also formed.  For example, if the acyl halide is an acyl chloride, HCl (hydrogen chloride or hydrochloric acid) is also formed.