Wednesday, 24 April 2013

1.40 explain, using dot and cross diagrams, the formation of covalent compounds by electron sharing

To draw a dot and cross diagram for a covalent bond, you need to draw the outer shells of the two atoms involved with an overlap, in this overlap should be the electrons they share. Half the electrons in the overlap should be dots and half crosses, because one electron in every pair comes from each atom. The rest of the electrons for the outer shell should be drawn on, one atom with dots, the other with crosses.

For example, H + Cl = HCl:
Inline images 1


You need to be able to do dot and cross for the following substances (comment if you need help with any):
i hydrogen
ii chlorine
iii hydrogen chloride
iv water
v methane
vi ammonia
vii oxygen
viii nitrogen
ix carbon dioxide
x ethane
xi ethene



16 comments:

  1. how do you do ethene/ethane? ty :)

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  2. The first picture won't load, what does it show?

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  3. oh it's ok dont worry, I got it :)

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  4. Hi ! the diagrams for this section aren't being show, is there anything you can do? thanks ! :)

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  5. This comment has been removed by the author.

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  6. the diagram is not loading. any solution

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  7. Remember:

    if you are not a pair, you share!

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  8. Remember:

    if you are not a pair, you share!

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  9. Remember:

    if you are not a pair, you share!

    ReplyDelete
  10. This website has all the diagrams =

    http://igcsechemistryrevision.weebly.com/particles--equations/139-explain-using-dot-and-cross-diagrams-the-formation-of-covalent-compounds-by-electron-sharing-for-the-following-substances-hydrogen-chlorine-hydrogen-chloride-water-methane-ammonia-oxygen-nitrogen-carbon-dioxide-ethane-ethene-in-order

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