Chemistry

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When 2.50g of an unknown solute is dissolved in 40.0g of ethanol the solution boils at 79.4C. The normal boiling point of this substance is 78.4C and it has a kb of 1.22C/m.
(a) What is the molality of this solution?
(b) What is the molecular weight of the solute?

  • Chemistry -

    delta T = Kb*m
    Solve for m

    molality = grams/molar mass
    solve for molar mass.

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