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    can someone please explain to me why H3O+ has a positive charge?
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    (Original post by cilla_e)
    can someone please explain to me why H3O+ has a positive charge?
    Heya, I'm going to put this in the chemistry forum for you as you should get more responses there.

    You should also check out the forum to see if there's any other threads there which might be helpful to you!

    http://www.thestudentroom.co.uk/forumdisplay.php?f=130
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    this is my educated guess so it might not be correct but this is what i'd assume
    • so H2O has 2 lone pairs right? that means it can form a dative covalent bond with something that has no electrons in outer shell.
    • when H loses an electron, it becomes H+ and has no electrons
    • this means it can form a dative bond with the O in H2O
    • because the H is charged, it makes the entire molecule positive
    • so H3O has a + charge
    i hope this helps!
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    (Original post by timelizard)
    this is my educated guess so it might not be correct but this is what i'd assume
    • so H2O has 2 lone pairs right? that means it can form a dative covalent bond with something that has no electrons in outer shell.
    • when H loses an electron, it becomes H+ and has no electrons
    • this means it can form a dative bond with the O in H2O
    • because the H is charged, it makes the entire molecule positive
    • so H3O has a + charge

    i hope this helps!

    thank you! this really helped
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    (Original post by cilla_e)
    thank you! this really helped
    If you draw out the structure of the hydroxonium ion H3O+, you will see that the central oxygen has 8 electrons in its outer shell while each hydrogen does not have any other electrons except the shared pair (which is part of the oxygen octet).

    Name:  H3O+.gif
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    Total protons in the structure = 8 + 1 + 1 + 1 = 11 protons
    Total electrons in the structure = 8(octet) + 2 (oxygen inner shell) = 10 electrons

    Hence one more proton than electron, overall 1+
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    (Original post by charco)
    If you draw out the structure of the hydroxonium ion H3O+, you will see that the central oxygen has 8 electrons in its outer shell while each hydrogen does not have any other electrons except the shared pair (which is part of the oxygen octet).



    Total protons in the structure = 8 + 1 + 1 + 1 = 11 protons
    Total electrons in the structure = 8(octet) + 2 (oxygen inner shell) = 10 electrons

    Hence one more proton than electron, overall 1+

    thank you! i think i got confused because the "+" is next to oxygen lol
 
 
 
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