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Homework Help: Chemistry help-forces

  1. May 7, 2005 #1
    Hi, I am soo stumped. Doing Grade 12 chemistry through independent learning with no teacher is TOUGH!
    1 question:
    It says:
    Identify two repulsive forces and two attractive forces that influences the formation of chemical bonds between two atoms.
    ~if anyone one could help itd be awesome!
    I found something on google, Im not sure if that is what they are asking for but it says: for attractive:
    -The orientation effect, or interaction between permanent dipoles;
    -The induction effect, or interaction between a permanent dipole and a temporary dipole;
    -The dispersion effect or the London force, interaction between temporary dipoles and induced dipoles.
    for repulsive
    -The orientation effect (dipole-dipole)
    -The induction effect (permanent dipole-induced dipole)
    -The dispersion effect or London force (temporary dipole-induced dipole)
    Last edited: May 7, 2005
  2. jcsd
  3. May 8, 2005 #2


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    You've provided the same 3 examples for attractive as well as repulsive forces...besides, do you know what they mean ?

    Think simpler : What the the main parts of an atom ? What forces exists between such parts ?
  4. May 8, 2005 #3
    Is this right?

    Yea.. I wasnt sure what those meant. I have read into it more considering what you said is this right??:

    Two attractive forces would be a small atom where the electrons are closely packed, and an electron, if the elctron approaches a small atom it can get close to the nucleus.

    Two repulsive forces would be a large atom where the electrons arent so closely packed, and an electron. If the electron approaches a large atom the electron will experience repulsion soner, and be further from the nuclues.
    Last edited: May 8, 2005
  5. May 8, 2005 #4


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    Okay, so far you know that each atom has a bunch of (negatively charged) electrons (E), and a (positive) nucleus (N).

    For a pair of atoms, let's call these : {E1,N1}, {E2,N2}

    How many forces can be drawn between the elements of the above two sets ? (recall set theory and cartesian products, if you wish to, but you don't have to) What are the natures of these forces ?
  6. Apr 28, 2007 #5
    ILC course

    Hi I'm taking the same course can you please help me with it.
  7. May 9, 2007 #6
    The problem I see so far is that you are talking about polarity (dipoles), these are effects between two MOLECULES, your question said between two ATOMS.
    I'm not sure exactly what they are looking for here, so I'm going to try to keep this simple but in bonding any two atoms, keep in mind that the two nuclei repel each other becuase they both have a positive charge. But a bond is made up of electrons, which have a negative charge. The electrons of one atom can attract the positive nucleus of another atom and create a bond. You can think of electrons as sort of an "electrical glue" between two nuclei, allowing the two nuclei to be drawn closer together. The more electrons involved, the stronger the bond. As far as I know these are the only atractive and repuslive forces that act in a bond between two atoms, perhaps they are looking for 1. repulsion of the two positive nuclei, 2. repulsion of the two electron clouds, 3. attraction of the nucleus of one atom to the other's electrons, and 4. attraction of the nucleus of an atom to its own electrons?

    Now WITHIN an atom, there is something known as electron shielding, where the negative charge of electrons close to the nucleus actually repels the electrons that are orbiting farther out (in higher energy levels), but I do not think this effect relates to bonding between two atoms, someone will have to check me on that.
    I'd be glad to help more if there is anyway you can be a little more specific with the question?
  8. Jan 9, 2008 #7
    check table 3-1 on page 78 of the textbook
  9. Apr 25, 2009 #8
    hahahaa, wow...
    the PERFECT answer is right there...

    thanks for the tip :)
  10. Jun 1, 2009 #9
    Okay this forum has actually helped me a lot in the past few weeks. (Have been working on retaking my grade 12 chemistry.) I am taking it at the adult education center in my city and this particular course asks you to read the text on several occasions. The only problem is that they do not provide you with the textbook anymore as it was a part of the old curriculum course.

    Does anyone know what is actually written in this mysterious textbook? I cannot see this 'table' so I have no clue where to go with this one.

    "Identify two repulsive forces and two attractive forces that influence the formation of chemical bonds between two atoms."

    All I can guess is that is has something to do with electronegativity values and the various types of bonding. (Perhaps something along the lines of:

    'Repulsive Forces - Large Atomic Radius & Full Valence Shell'
    'Attractive Forces - Small Atomic Radius & SomethingSomething' )

    I have been out of high school for a few years now so I do not remember doing any work on set theory and Cartesian products if that is supposed to help me. Any websites I can take a look at or anyone with somewhere I can get the actual text from this textbook? Thanks.
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