The reaction of 1-chlorobutane with sodium ethoxide is a nucleophilic substitution reaction. In this reaction, the nucleophile, which is the ethoxide ion (EtO-), attacks the electrophile, which is the 1-chlorobutane molecule. The nucleophile displaces the leaving group, which is the chloride ion (Cl-), and forms a new bond with the carbon atom that was originally bonded to the leaving group. The products of this reaction are ethyl butyl ether and sodium chloride.

The reaction can be represented as follows:

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CH3CH2CH2CH2Cl + NaOEt → CH3CH2CH2CH2OEt + NaCl

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The rate of this reaction is influenced by several factors, including the concentration of the reactants, the temperature, and the solvent. The reaction is typically carried out in a polar solvent, such as ethanol or dimethylformamide, which helps to dissolve the reactants and stabilize the transition state. The reaction rate also increases with increasing temperature.