At 20 °C, a 2.32 mol L^-1 aqueous solution of ammonium chloride has a density of 1.0344 g mL^-1. What is the molality of ammonium chloride in the solution? The formula weight of NH₄Cl is 53.50 g mol^-1. A)2.55 B)0.0449 C)2.32 D)0.446 E)12.00

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Quizplus · Accepted Answer

To find molality, we need moles of solute per kg of solvent. First, calculate the mass of the solution: 1.0344 g/mL * 1000 mL = 1034.4 g. Moles of NH4Cl = 2.32 mol/L * 1 L = 2.32 mol. Mass of NH4Cl = 2.32 mol * 53.50 g/mol = 124.12 g. Mass of water = 1034.4 g - 124.12 g = 910.28 g = 0.91028 kg. Molality = 2.32 mol / 0.91028 kg = 2.55 mol/kg.