Is the leakage you refer to an actual physical leakage (i.e. diffusion) of gas into or out of the tubes?
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Down with categorical imperative!
flutzpah@yahoo.com
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________________________________
From: Bernard Cleyet <bernardcleyet@redshift.com>
To: Forum Physics Educators <phys-l@carnot.physics.buffalo.edu>
Sent: Thu, December 3, 2009 10:15:10 AM
Subject: [Phys-l] size controversy
W / o resorting to the authority of Google to settle the dispute on
tap-l, I appeal to the wisdom of phys-l. (especially the chemist
among us)
Which has a larger atomic radius H or He? The question relates to
leakage in spectrum tubes. One claims goes smaller left to right
(greater Z in nucleus) while another appeals to greater electronic
shielding, Both ignore a possible effect of a "filled" shell.
bc even too lazy to look in his Eisberg & Resnick "Quantum Physics"
and read Schiff over 50 years ago