The balanced chemical equation for the preparation of 2,4-dinitrophenol from phenol and nitric acid is:C6H5OH + 2 HNO3 C6H3N2O5 + 2 H2OPhenol + 2 Nitric acid 2,4-Dinitrophenol + 2 WaterFor the synthesis process to occur efficiently, the reaction conditions should include:1. Temperature: The reaction should be carried out at a low temperature, typically around 0C to 5C. This is to prevent the formation of undesired by-products, such as trinitrophenol.2. Concentration of nitric acid: Using a mixture of concentrated nitric acid around 65-70% and sulfuric acid around 95-98% as a nitrating agent is recommended. The sulfuric acid acts as a dehydrating agent, which helps to control the reaction rate and improve the yield of 2,4-dinitrophenol.3. Reaction time: The reaction should be allowed to proceed for a sufficient amount of time, typically a few hours, to ensure complete nitration of the phenol.4. Stirring: Constant stirring during the reaction helps to ensure even distribution of the reactants and improve the yield of the desired product.5. Post-reaction treatment: After the reaction is complete, the mixture should be poured into an ice-water mixture to precipitate the 2,4-dinitrophenol. The precipitate can then be filtered, washed, and dried to obtain the pure product.