Re: pinhole ionic compounds

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From: Geoff Ruth (gruth@leadershiphigh.org)
Date: Fri Dec 12 2003 - 14:27:44 PST 

Message-Id: <p05210610bbfff101c218@[192.168.123.175]>
Date: Fri, 12 Dec 2003 14:27:44 -0800
From: Geoff Ruth <gruth@leadershiphigh.org>
Subject: Re: pinhole ionic compounds

Neil --

But you can get two machined metals together class enough to fuse and
become one seamless piece of metal -- isn't this called cold welding?
I know metals are much stronger & less brittle, so that they can be
compressed, but I thought that you could actually have metals fuse
just be pressing them together, provided that each surface was
machined & polished to a high enough degree.

What's the difference between the two cases, or is my recollection wrong?

-- Geoff

>Hi Sally,
>You cant get the two cubes close enough to get the electrostatic forces to
>take hold. These forces decay rapidly with distance and you cant
>push the cubes
>hard enough without destroying them to get ionic bonds to form. However, ions
>in solution can get close enough to a crystal face to form an ionic bond.
>Neil Fetter
>
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