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    Hi there,

    I'm quite stuck at suggesting formulas for compounds and such.
    For example:
    one question in the edexcel unit 1 exam said:
    Which of the following formulae for compounds of germanium, Ge, is unlikely to be correct, given the position of germanium in the periodic table:

    A) GeF3
    B) GeS2
    C) GeO2
    D) GeH4

    the answer is A but i'm not sure why!
    Also, one said, suggest a formula of Gallium chloride and one answer is GeCl3 or Ge2Cl6.

    Please help!
    Rep for best explanation.

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    i did this paper as a mock exam and i got it right due to my elimination process

    Ge has a total of 32 electrons but only 4 is on the outer shell coz it's in group 4.
    If Ge formed with F it would only have 7 electrons and therefore it would not obey the octet rule and so it's unlikely to form
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    Germanium has got 4 electrons in it's outer most shell
    F has 1 electron in it's outer most shell and there's three of them
    If they form three covalent bonds in total you get 7 electrons

    This is not completing the outer most shell, you need 8 to fill it up not 7.

    That is why A is the answer

    Did that help?
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    (Original post by EffKayy)
    The outer shell of Germanium has got 6 electrons in it
    No it doesn't. It has 2 4s electrons and 2 4p electrons.

    Gallium trichloride exists as GaCl3 in the gas phase, and Ga2Cl6 in the solid phase, but I doubt they'd expect you to know that.
 
 
 
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