The nucleophilic substitution reaction of 2-bromobutane with sodium hydroxide in ethanol follows the SN2 Substitution Nucleophilic Bimolecular mechanism. Here's a step-by-step description of the mechanism:1. Sodium hydroxide NaOH dissociates into sodium Na+ and hydroxide OH- ions in the ethanol solvent. The hydroxide ion acts as a nucleophile in this reaction.2. The nucleophile OH- attacks the electrophilic carbon atom the one bonded to the bromine in 2-bromobutane from the backside, opposite to the leaving group Br- . This backside attack leads to the inversion of the stereochemistry at the electrophilic carbon.3. As the nucleophile forms a bond with the electrophilic carbon, the carbon-bromine bond starts to break, and the bromide ion Br- is released as the leaving group.4. The product formed is 2-butanol, with the hydroxide ion now bonded to the electrophilic carbon, and the bromide ion is released as a byproduct. The sodium ion Na+ associates with the bromide ion Br- to form sodium bromide NaBr as a side product.Overall reaction:2-bromobutane + NaOH 2-butanol + NaBrThis SN2 mechanism occurs in a single concerted step, with the nucleophile attacking and the leaving group departing simultaneously. The reaction rate is dependent on the concentration of both the nucleophile and the substrate, hence the term "bimolecular" in the SN2 mechanism name.