Chem

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a solution containing 100g of unknown liquid and 900g water has a freezing point pf -3.33 C. given kf=1.86 degrees c for water, the moelcular weight of the unknown liquid is what?

  • Chem -

    delta T = Kf*molality
    Solve for m

    m = #moles/kg solvent
    Substitute m and kg solvent, solve for # moles.

    # moles = grams/molar mass
    You have #moles and grams, solve for molar mass.

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