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The melting point of a pure solvent (kf=1.79°C/m) is -116.3°C. If 312 g of an ionic solid (i=2.6) is added to 567.7 g of the solvent, the new melting point is -101.6°C. What is the molar mass of the ionic solute?

  • Chemistry -

    delta T = i*Kf*molality
    Substitute and solve for molality.

    molality = moles/kg solvent. You have molality and kg solvent, solve for moles.

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

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