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Bond angles of cyclopropane

  1. Feb 18, 2012 #1
    Cyclopropane is a cycloalkane with three carbon atoms. Each carbon is bonded to two hydrogens as well as the other two carbons, forming a triangular bond between the three carbons.

    Each carbon has a tetrahedral molecular geometry since it has sp3 hybrization. However, I am rather confused about the bond angles that the carbon atoms make with another. I am talking about the C-C-C angles.

    Because the structure is tetrahedral, the bond angles should be 109.5 degrees. But because the cyclopropane is an equilateral triangle, they must be 60 degrees. Which is correct and why not the other?


  2. jcsd
  3. Feb 18, 2012 #2
    I believe you should be able to find a reasonable answer to your questions here:

    Cyclopropane Ring Strain.

    In short, the angles between the carbons are 60°. Cyclopropane is notoriously reactive (and its C-C bonds are weakened relative to other cycloalkanes) as a result.
  4. Feb 19, 2012 #3
    Thank you so much it all makes sense now. Just curious, under what branch of chemistry would you study these sorts of things, such as the angle strains of cycloalkanes? Organic?


  5. Feb 21, 2012 #4


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