[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Water - getting decidedly off-topic...



> From: "S. Hieber" <shieber at yahoo_com>
> Subject: Re: Density of Water -- & the Density of Science
> 
> For that matter, why aren't the Hs on an H2O molecule
> precisely 120 degrees apart?

	One wouldn't expect 120 degrees.  Simple molecular orbital theory
would predict the "tetrahedral" angle 109 degees and change, but the
elecron pairs that _aren't_ bonding O to H - the "lone pairs" are held
closer in and repel each other more strongly, pushing the OH bonds
closer together.  The angle ends up at 104.5 degrees.

-- 
Paul Sears        Ottawa, Canada