RE: Chemistry Question

[Bill_Goldsmith@radian.com]

Multiply thickness by surface area to yield volume.  If it is anhydrous
ThF4, multiply volume (cm3) by 6.32 (s.g.) to yield grams ThF4.  Assuming it
is all Th-232 in the coating, multiply grams of ThF4 by 232 and divide by
308 (i.e., 232+19*4) to yield grams of Th232.  Divide grams Th232 by 232 to
yield moles and multiply moles by 6.02E23 to yield atoms.  Multiply by decay
constant to yield activity; convert activity to pCi.
Bill Goldsmith
Radian International LLC
423-220-8265
bill_goldsmith@radian.com <mailto:bill_goldsmith@radian.com> 



		-----Original Message-----
		From:	Tad Blanchard
[mailto:Tad.M.Blanchard.1@gsfc.nasa.gov]
		Sent:	June 23, 1999 08:42
		To:	Multiple recipients of list
		Subject:	Chemistry Question

		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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