The yield of benzocaine obtained from the synthesis reaction of p-aminobenzoic acid and ethanol depends on the specific reaction conditions used, such as temperature, solvent, and reactant ratios. It is difficult to provide an exact yield percentage without knowing the precise conditions of the reaction. However, I can provide some general information on how the yield may vary with changes in these reaction conditions.1. Temperature: The reaction between p-aminobenzoic acid and ethanol is an esterification reaction, which is generally favored at higher temperatures. Increasing the temperature can increase the reaction rate and potentially improve the yield of benzocaine. However, excessively high temperatures may cause side reactions or degradation of the reactants or product, which could decrease the yield.2. Solvent: The choice of solvent can significantly impact the yield of benzocaine. A suitable solvent should dissolve both reactants and not interfere with the reaction. Common solvents used for esterification reactions include polar aprotic solvents such as dimethylformamide DMF or dimethyl sulfoxide DMSO . The solvent should also have a boiling point higher than the reaction temperature to avoid evaporation during the reaction. Changing the solvent may affect the solubility of the reactants, the reaction rate, and the overall yield of benzocaine.3. Reactant ratios: The stoichiometry of the reactants can also influence the yield of benzocaine. Ideally, the reaction should have a 1:1 molar ratio of p-aminobenzoic acid to ethanol. However, in practice, it is common to use an excess of one reactant to drive the reaction to completion and improve the yield. For example, using an excess of ethanol can help shift the equilibrium towards the formation of benzocaine. However, using too much excess of a reactant can lead to side reactions or difficulties in product purification, which may decrease the overall yield.In summary, the yield of benzocaine from the synthesis reaction of p-aminobenzoic acid and ethanol can be influenced by various reaction conditions, including temperature, solvent, and reactant ratios. Optimizing these conditions can help improve the yield, but it is essential to consider the potential trade-offs and limitations associated with each factor.