To calculate the mass of 2,4-dinitrophenol that can be obtained from 5 grams of phenol, we need to use stoichiometry. First, we need to find the balanced chemical equation for the synthesis of 2,4-dinitrophenol from phenol and nitric acid.The balanced chemical equation is:C6H5OH phenol + 2 HNO3 nitric acid C6H3N2O5 2,4-dinitrophenol + 2 H2O water Now, we need to find the molar masses of phenol and 2,4-dinitrophenol.Phenol C6H5OH : 6 12.01 + 5 1.01 + 16.00 = 94.11 g/mol2,4-Dinitrophenol C6H3N2O5 : 6 12.01 + 3 1.01 + 2 14.01 + 5 16.00 = 184.11 g/molNext, we need to convert the mass of phenol 5 grams into moles:moles of phenol = mass of phenol / molar mass of phenolmoles of phenol = 5 g / 94.11 g/mol = 0.0531 molAccording to the balanced chemical equation, 1 mole of phenol reacts to produce 1 mole of 2,4-dinitrophenol. Therefore, the moles of 2,4-dinitrophenol produced will be the same as the moles of phenol used:moles of 2,4-dinitrophenol = 0.0531 molNow, we can convert the moles of 2,4-dinitrophenol into mass:mass of 2,4-dinitrophenol = moles of 2,4-dinitrophenol molar mass of 2,4-dinitrophenolmass of 2,4-dinitrophenol = 0.0531 mol 184.11 g/mol = 9.77 gTherefore, the mass of 2,4-dinitrophenol that can be obtained from 5 grams of phenol and excess nitric acid is approximately 9.77 grams.