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Homework Help: Molarity of solution

  1. Sep 1, 2008 #1
    Here is the problem..

    Calculate the molarity of a 0.342M sugar (C12H22O11) solution that has a density of 1.12g/mL.

    The answer is 0.341m but I don't know the steps..

    Please help me with this problem :(
  2. jcsd
  3. Sep 2, 2008 #2


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    You probably asked for "Molarity" when you meant to ask for "Molality".
    Starting with your 0.342 moles per liter of sugar solution, use the formula weight to find GRAMS of sugar per liter of solution. You need to calculate the formula weight of the compound from the empirical formula. Can you do the rest?
  4. Sep 2, 2008 #3


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    The bolded thing is the abbreviation for molarity. I assume that the question actually asked you to solve for the molality (moles per Kg of solution).

    Can you see that the density of the solution will be helpful? If each mL of solution weighs 1.12 g, how much will 1000 mL weigh? And how much sugar will be in that 1000 mL (or liter)?
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