The concentration of HCl in a solution that is prepared by dissolving 5.5 g of HCl in 200 g of C₂H₆O is ________ molal. A)27.5 B)7.5 × 10^-4 C)3.3 × 10^-2 D)0.75 E)1.3

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Quizplus · Accepted Answer

Molality is calculated as moles of solute per kilogram of solvent. The molar mass of HCl is approximately 36.46 g/mol. Thus, 5.5 g of HCl is 5.5 / 36.46 = 0.151 moles. The mass of ethanol (C2H6O) is 200 g, which is 0.2 kg. Therefore, the molality is 0.151 moles / 0.2 kg = 0.755 mol/kg, which rounds to 0.75 molal.

The Concentration of HCl in a Solution That Is Prepared