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Sphere equation?

  1. Oct 24, 2005 #1

    Math Is Hard

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    OK, I'm clueless. I have this one homework problem where I am asked to represent a reaction with a "sphere equation". I have no idea what this is and I can't locate it in my book. Wasn't mentioned during lecture either.
    Does anyone know what this means? :confused:

    Here's the whole problem (maybe it will make sense in context):

    a) write a chemical equation for the complete combustion of ethane.
    b) represent this equation with Lewis structures.
    c) represent this reaction with a sphere equation.
     
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  3. Oct 24, 2005 #2

    Tide

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    I think they are asking you to draw a picture of the reaction using spheres to represent the atoms of each molecule.
     
  4. Oct 24, 2005 #3

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    hey Tide - thanks for responding. Do you mean kinda like a ball and stick diagram?
     
  5. Oct 24, 2005 #4

    Tide

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    Yes - but without the sticks!
     
  6. Oct 24, 2005 #5

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  7. Oct 25, 2005 #6

    Chronos

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    Use x^2 + y^2 + z^2 = c to define the boundaries of spherical surfaces.
     
  8. Oct 25, 2005 #7

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    OK, it seems all she was looking for was a "ball and stick" drawing for each molecule in the reaction, but my space filling representations were acceptable. Darn chemistry! Too much artwork!
     
  9. Oct 25, 2005 #8

    Gokul43201

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    MIH : What you want is called a Newman Diagram or Newman representation. That only tells you the conformational arrangement of atoms in a molecule (like ethane), but can not represent a reaction.

    There's no such thing in chemistry as a sphere equation for a chemical reaction. At best, you can write an equation of state based on a hard-sphere interaction model, but that has nothing to do with this question.
     
    Last edited: Oct 25, 2005
  10. Oct 25, 2005 #9

    Astronuc

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  11. Oct 25, 2005 #10

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    ahh yes.. Newman Diagrams..
    [​IMG]
    Never heard of 'em!!!!
    umm.. before you guys get too carried away, I should tell you this is a class for NON-science majors. :redface: I am lazy as hell, and want to do the LEAST amount of chemistry possible. Here's the description:
    And the book is from our friends at The American Chemical Society.
    Chemistry in Context.
     
  12. Oct 25, 2005 #11

    Gokul43201

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    That's the one !!!

    Newman diagrams are very simple things with a fancy name. It's one of the first things you learn in organic chemistry.

    Here's what one looks like :

    [​IMG]
     
  13. Oct 25, 2005 #12

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    hmm.. y'know Gokul, that doesn't look quite as scary as I imagined. I was curious about it, so I found some explanations of the diagrams here:
    http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch03/ch3-diagrams.html
    so if I understood what they said correctly, that intersection in the front (of the diagram you posted) represents one carbon atom, and it has CH3, Br, and H attached to it. Then the circle would be another carbon atom (behind it) that the front one is bonded to, and it has CH3 and two H atoms attached to it.
    [​IMG]
    So it's kind of like a perspective drawing?
     
  14. Oct 25, 2005 #13

    Gokul43201

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    Yup. That's all it is !
     
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