Chemistry

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Calculate the molar mass of a compound that raises the boiling point of water to 100.15oC when 40.5 g of the compound is dissovled in 500 g of water.

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A mass of 41 g of an unknown nonelectrolyte is dissolved in 429 g naphthalene. The nonelectrolyte lowers naphthalene's freezing point by 7.2 oC. What is the molecular mass of the unknown substance? (Kf = 6.8 oC/mola

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    #1.
    a. delta T = Kb*molality
    You know delta T and Kb, solve for molality.
    b. Then molality = mols/kg solvent.
    You know molality and kg solvent, solve for mols.
    c. mols = grams/molar mass. You know mols and grams, solve for molar mass.

    #2.
    Same kind as #1. Post your work if you get stuck.

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