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Homework Help: Empirical and Molecular Forumla calculation

  1. Oct 23, 2008 #1
    1. The problem statement, all variables and given/known data

    Reductic acid contains 52.63% carbon, 5.30% hydrogen and 42.07% oxygen by mass.
    a) Determine the empirical formula of reductic acid

    b) If 1.23 g of reductic acid contains 3.25x10^22 atoms of carbon, what is the molecular formula of reductic acid ?

    c) Calculate the mass of one molecule of reductic acid.


    2. Relevant equations

    -

    3. The attempt at a solution

    I already found that the empirical formula and found that to be C5H6O3. But I can't seem to get the other parts. Thanks for the help.
     
  2. jcsd
  3. Oct 24, 2008 #2

    GCT

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    Science Advisor
    Homework Helper

    Use the molecular mass of the empirical formula to find the number of carbon atoms that there would be in 1.23 g and then compare this to the actual number of carbons given in the problem

    e.g.

    1.23 g ( moles / g = MW of C5H6O3 ) = moles of C5H6O3

    convert this to atoms of C5H6O3 and then this to atoms of Carbon = x

    3.25 X 10 ^ 22 atoms of carbon / x = the number factor to multiply your empirical formula to find the molecular formula.




    For the next part simply use Avogadro's number.
     
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