the lewis structure for the polyatomic hydronium cation is H₃O⁺.
The hydronium ion is written as :
H₃O⁺, to fulfil the octet rule there will be 8 valence electrons.
number of valence electrons are :
number of valence electron for 1st H atom = 1
number of valence electron for 2nd H atom = 1
number of valence electron 3rd H atom = 1
number of valence electron s for O = 6
the + sign show that there is loss of one electron, the more electronegative atom is Oxygen atom that means O atom is the central atom. therefore it has 8 valence electrons. the lewis structure is shown as below :
[ H - O : - H ]⁺
|
H
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