ap chemistry

posted by .

A 4.47 g sample of a molecular compound is dissolved in 96 g of tetrachloromethane. The normal boiling point of the solution is 61.51 degrees celcius, the normal boiling point for CCl4 is 61.2 degrees celsius. The boiling point constant for CCl4 is 4.95K*kg/mol. What is the molar mass of the compound? Answer in units of g/mol

I know you have to use the formula:
delta Tb = iKbm but I have no clue how start or find the molality.

PLEASE HELP

  • ap chemistry -

    Note the correct spelling of celsius.

    Why don't you start with delta T = i*Kb*m
    You can calculate delta T, i = 1 since it is a molecular compound, you know Kb and solve for m.
    Then m = mols/kg solvent. You know m and kg solvent, solve for mols.
    Then mols = grams/molar mass. You know mols and grams, solve for molar mass.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. chemistry

    How much heat is required to vaporize 3.50L of at its normal boiling point?
  2. chemistry

    How much heat is required to vaporize 3.50L of at its normal boiling point?
  3. Chemistry

    How much heat is required to vaporize 1.00 L of CCl4 at its normal boiling point?
  4. chemistry

    dimethylglyoxime is used as a reagent in qualitative analysis to precipitate the nickel(II) ion. a solution is made by dissolving 57.0 grams of DMG in 430.0 g of ethanol. (a) what is the mole fraction of DMG in this solution?
  5. Chemistry

    Which of the following statements about boiling points are false: A. the boiling point of 0.1 m KF(aq) is lower than the boiling point of 0.1 m ethanol(aq) B. the boiling point of a 0.5 m aqueous solution of NaOH is the same as the …
  6. chemistry

    A 2.97 g sample of a molecular compound is dissolved in 103 g of tetrachloromethane (carbon tetrachloride). The normal boiling point of the solution is 61.51C, the normal boiling point of CCl4 is 61.2C. The boiling point constant …
  7. AP Chem

    A 1.73 g sample of a molecular compound is dissolved in 105 g of tetrachloromethane (carbon tetrachloride). The normal boiling point of the solution is 61.51C, the normal boiling point of CCl4 is 61.2C. The boiling point constant …
  8. Chemistry

    A 1.065-g sample of an unknown substance is dissolved in 30.00 g of benzene; the freezing point of the solution is 4.25 degrees C. The compound is 50.69% C, 4.23% H, and 45.08% O by mass. Info you might need on benzene: Normal Freezing …
  9. chemistry

    Which of the following statements about boiling points are true?
  10. chemistry

    A 2.00 g sample of a particular compound was dissolved in 15.0 g of carbon tetrachloride. The boiling point of this solution was determined to be 77.85ºC. For pure CCl4, TB = 76.50ºC and KB = 5.03°C·kg/mol Calculate the boiling …

More Similar Questions