To calculate the yield of 2,4-dinitrophenylhydrazine, we first need to determine the balanced chemical equation for the reaction and then use stoichiometry to determine the theoretical yield. Finally, we can compare the theoretical yield to the actual yield to determine the percentage yield.The balanced chemical equation for the reaction between 2,4-dinitrochlorobenzene and hydrazine is:C6H3ClN2O4 + N2H4 C6H3N4O4 + HClNow, we need to determine the number of moles of 2,4-dinitrochlorobenzene. The molecular weight of 2,4-dinitrochlorobenzene is:C: 12.01 g/mol * 6 = 72.06 g/molH: 1.01 g/mol * 3 = 3.03 g/molCl: 35.45 g/mol * 1 = 35.45 g/molN: 14.01 g/mol * 2 = 28.02 g/molO: 16.00 g/mol * 4 = 64.00 g/molTotal molecular weight = 72.06 + 3.03 + 35.45 + 28.02 + 64.00 = 202.56 g/molNow, we can determine the number of moles of 2,4-dinitrochlorobenzene:moles = mass / molecular weightmoles = 1.00 g / 202.56 g/mol = 0.00494 molAccording to the balanced chemical equation, 1 mole of 2,4-dinitrochlorobenzene reacts with 1 mole of hydrazine to produce 1 mole of 2,4-dinitrophenylhydrazine. Therefore, the number of moles of 2,4-dinitrophenylhydrazine produced is equal to the number of moles of 2,4-dinitrochlorobenzene reacted, which is 0.00494 mol.Now, we need to determine the molecular weight of 2,4-dinitrophenylhydrazine:C: 12.01 g/mol * 6 = 72.06 g/molH: 1.01 g/mol * 3 = 3.03 g/molN: 14.01 g/mol * 4 = 56.04 g/molO: 16.00 g/mol * 4 = 64.00 g/molTotal molecular weight = 72.06 + 3.03 + 56.04 + 64.00 = 195.13 g/molNow, we can determine the theoretical yield of 2,4-dinitrophenylhydrazine:theoretical yield = moles * molecular weighttheoretical yield = 0.00494 mol * 195.13 g/mol = 0.963 gSince we are given an excess of hydrazine, we can assume that all of the 2,4-dinitrochlorobenzene reacts to form 2,4-dinitrophenylhydrazine. Therefore, the actual yield is equal to the theoretical yield, which is 0.963 g.