Re: Chemistry Question

[steve hand <hand@wam.umd.edu>]

Tad:

    Atoms have diameters on the order of angstroms (A) (with a dot over the top).  If you can look up the diamater of the thorium-fluoride then you can calculate the number of atoms of thorium.  1A = 10E-10 meters.  Knowing your
dimensions for the lens you can calculate the total on the face.  Thorium is listed as having a radius of 0.95 A.

    Hope this helps a little.

Steve Hand
Radiation Safety
University of Maryland

Tad Blanchard wrote:

> Hello All,
>
> If a glass lens is coated with 1000 Angstroms of Thorium-Fluoride, how do we determine the total activity (picocuries?) of the Thorium in the coating?
>
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