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Hexachlorophene is used as a disinfectant in germicidal soaps. What mass of hexachlorophene (406.9 g/mol) must be added to 125 g of chloroform to give a solution with a boiling point of 62.60°C?

1 Answer

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Answer: 18 grams

Step-by-step explanation:

Elevation in boiling point:


\Delta T_b=i* k_b* m


T_b-T^o_b=i* k_b* (w_2* 1000)/(M_2* w_1)

where,


T_b = boiling point of solution =
62.60^oC


T^o_b = boiling point of chloroform =
61.2^oC


k_b = boiling point constant of chloroform =
3.88^oC/m

m = molality

i = Van't Hoff factor = 1 (for non-electrolyte)


w_2 = mass of solute (hexachlorophene ) = x g


w_1 = mass of solvent (chloroform) = 125 g


M_2 = molar mass of solute (hexachlorophene ) =406.9

Now put all the given values in the above formula, we get:


(62.60-61.2)^oC=1* (3.88^oC/m)* ((xg)* 1000)/(406.9* (125g))


1.40^oC=1* (3.88^oC/m)* ((xg)* 1000)/(406.9* (125g))


x=18g

Therefore, the mass of hexachlorophene that must be added is 18 grams

User Alex Derkach
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