Mark -
I'm guessing that the model you're building has
little wooden balls (or something like that) for the electrons and the
protons. This is a pretty common way of looking at atoms, although (as
we're going to get to soon) it's not actually right. One thing we can
say is that protons are much heavier than electrons (1800 times
heavier!). So in most home-made models, the electron "ball" is much
smaller than the proton.
Protons do have a definite size. They
are made up of stuff, quarks and gluons, which move around each other.
Electrons (on the other hand) are, as far as we know, "point
particles." That means there's nothing inside of one - and we can't
really say how "big" one is. And because they are so much lighter, they
are harder to pin down - they aren't little "balls" at all, and they
don't sit still, ever. They inhabit "clouds" or "orbitals" surrounding
the nucleus; the size of an atom is determined by how big these clouds
are.
For more information on building a model atom the way it
really looks, check out the answer to the questions
How to Build a Model Atom and
Picture of an Atom.
For more information on Titanium, check out
www.WebElements.com. (Note: the picture of the nucleus / electrons on the right side of this page is totally out of proportion.)
-Tamara, Tom, and Tim
(published on 10/22/2007)
