[Sarcofago]

Hello, everybody I do hope that you will be able to solve my problem cause obviously I cannot...
Well we take the Oxygen in the water molecule - we got two binding electrons and two lone pair electrons.. that's brilliant, but then we have got the hydronium ion - H3O, how is that happening that we have got only two binding electrons in the oxygen and at the same time oxygen is bound to three atoms of Hydrogen... it is the analogous situation with the hydroxide ion... I would appreciate help of any kind !!!

[Sarcofago]

And how is that HO- got three lone pair electrons? I definitely miss something. I read the polar covalent bonds but ...

[tamim83]

The oxygen in water has 2 lone pairs, a total of 4 electrons and yes two of oxygens electrons are participating in bonding with the two hydrogens.  So when a water molecule picks up a hydrogen cation to form H3O+, there is 1 lone pair left over, the other formed a bond with the hydrogen cation.  This is called a Lewis acid base reaction since it involves electron pairs; the water is donating an electron pair to the hydrogen cation. 

And yes, something similar happens with OH-; it has three lone pairs that can be donated to an acceptor like a hydrogen cation or metal cation. 

[Sarcofago]

Hi, thank You tamim83, I have misunderstood the information that I am reading from the book. I think I got it now. Thanks once again!

[azmanam]

I think you're getting hung up on the terms.  Just because we classify a pair of electrons as bonding or non-bonding, does not imply that those electrons cannot be classified as something else after a chemical transformation.  The classification is a description of the molecule at that time and is not intended to describe those electrons under all conditions/bonding patterns.

Non bonding electron pairs can become sigma bonding electrons.  Pi bonding electrons (double bond) can become sigma bonding electrons.  And vice versa.  Happens all the time.  We've just described every chemical reaction.  Ever.

[Sarcofago]

I was wondering if we got H30,why can't we have H40 ... in case we got a free pair left but I found that and if someone is curious...

"So, why not H4O2+? Well, there are electrostatic arguments. Putting positive charges together is energetically expensive. There are space arguments. The proton once it is "coordinated" to the water molecule is no longer "naked". It has electrons which means that it is quite large - certainly as large as the other two protons which help to define the tetrahedral structure of water molecules. But likely the most important consideration is that water is 55.5 Molar. Even at an acid strength of 1 M, there are 55.5 water molecules to each proton. That is a lot of competition and it is unlikely that you are going to find protons doubling up! After all, it is energy expensive and there is no need with all of the available partners."

http://www.madsci.org/posts/archives/2001-09/1001450718.Ch.r.html - the source.

[AWK]

H₃O⁺, H₅O₂⁺ you can find in the crystal structures of some strong acids. The most known is HClO₄ hydrate, but in fact (H₃O⁺ ClO₄^-). See also structure of ice in which each oxygen atom is coordinated by (2+2) hydrogen atoms.

Correction: 2 moved down from superscript to subscript in H₅O₂⁺

[Borek]

I was wondering if we got H30,why can't we have H40 ...

Please, don't ignore charges in your posts.

[Mitch]

H₄0²⁺ would be interesting, I don't think anyone has tried to make it. Feel free to try.

[heliosaurum]

H₄0²⁺ would be interesting, I don't think anyone has tried to make it. Feel free to try.

I think someone had tried it before but no one success...