Hexachlorophene is used as a disinfectant in germicidal soaps. What mass of hexachlorophene (ℳ = 406.9 g/mol) must be added to 125 g of chloroform to give a solution with a boiling point of 62.60°C? K_b = 3.63°C/m, boiling point of pure chloroform = 61.70°C A)12.6 g B)17.2 g C)31.0 g D)34.4 g E)101 g

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The correct answer is A because the boiling point elevation is given by the equation ΔTb = Kb * molality, where ΔTb is the change in boiling point, Kb is the boiling point elevation constant, and molality is the concentration of the solution in molality. We can rearrange this equation to solve for molality: molality = ΔTb / Kb. We know that the change in boiling point is 62.60°C - 61.70°C = 0.90°C, and the boiling point elevation constant for chloroform is 3.63°C/m. Therefore, the molality of the solution is 0.90°C / 3.63°C/m = 0.248 m. We can then use the molality to calculate the mass of hexachlorophene that must be added to the solution: mass = molality * molar mass * volume of solution. We know that the volume of the solution is 125 g, and the molar mass of hexachlorophene is 406.9 g/mol. Therefore, the mass of hexachlorophene that must be added to the solution is 0.248 m * 406.9 g/mol * 125 g = 12.6 g.

Hexachlorophene Is Used as a Disinfectant in Germicidal Soaps