1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Find the Formula of compound X

  1. Aug 11, 2010 #1
    1. The problem statement, all variables and given/known data
    When 1.11 g of a compound X is completely burnt,1.98 g of carbon dioxide and 0.81 g of water were formed. Which of the following could be X?

    A. CH[tex]_{3}[/tex]CH[tex]_{2}[/tex]CH[tex]_{3}[/tex]
    B. CH[tex]_{3}[/tex]CH[tex]_{2}[/tex]COOH
    C.CH[tex]_{3}[/tex]COCH[tex]_{3}[/tex]
    D.C[tex]_{6}[/tex]H[tex]_{5}[/tex]CH[tex]_{2}[/tex]OH


    3. The attempt at a solution

    I tried

    C[tex]_{x}[/tex]H[tex]_{y}[/tex] + {x+[tex]\frac{y}{4}[/tex]}O[tex]_{2}[/tex] [tex]\rightarrow[/tex]
    XC0[tex]_{2}[/tex] + [tex]\frac{y}{2}[/tex]H[tex]_{2}[/tex]O

    but how about the oxygen atom(s) within compound X?

    How can I form a balanced equation for X containing O?

    Sorry about the equations and formulae... can't get the subscripts in the right positions.
     
    Last edited: Aug 11, 2010
  2. jcsd
  3. Aug 11, 2010 #2

    alxm

    User Avatar
    Science Advisor

    The only things in the product that you can be absolutely sure come from the reactant is the carbon and hydrogen. So, from the water and CO2, calculate how many moles of C and H you had to begin with. What's the mass of this amount of carbon and hydrogen - is it enough to account for all of the 1.11 g you had to begin with?
     
  4. Aug 12, 2010 #3
    Got it. Useful hint.Thanks. Answer's B. :smile:
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Find the Formula of compound X
  1. Compound Formulas (Replies: 1)

Loading...