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Homework Help: Which compound is LESS stable?

  1. Apr 21, 2008 #1
    below are two simple compounds. this is from a first semester general chemistry test and there were four compounds total all with the same number of C H and O we had to tell which one was least stable and why.

    I don't remember the other two because both had a formal charge of 0 on everything while these two had a +1 on the O (most of the time not a good sign) and -1 on the C.

    I picked the first one as less stable because of the formal charges and because I was used to seeing the hydrogen atoms bonded to the C.

    Can anyone tell me if I was right and what is the best way to approach these problems aside from straight formal charges?
     

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  2. jcsd
  3. Apr 22, 2008 #2

    GCT

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    Does the top carbon have a hydrogen on it? Please make sure that all structures have the right numbers of hydrogen.
     
  4. Apr 22, 2008 #3
    What do you mean? notice that there are two structures seperated by a bit of whitespace. The top structure has no hydrogens on the carbons. Would you like me to draw the lone pairs?
     
  5. Apr 22, 2008 #4
    I drew the lone pairs on the top one:
     

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  6. Apr 23, 2008 #5

    GCT

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    This problem is a test of your understanding of the concept of oxidation states - there a rules in calculating these values and it does involve considering the formal charge - oxidation states also takes into account the type of atoms that a particular central atom is bonded to as well as its bonding arrangement while formal charge takes into account soley the bonding arrangement of the particular atom.
     
    Last edited: Apr 23, 2008
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