Dr. Polemic wrote:

The information on this web page doesn't indicate directly what the vapor pressure of
cadmium is at 20 degrees, but extrapolating the numbers in the table gives a value of
10^-12 torr at 30 degrees. It takes more than a "nice little vacuum pump" to achieve
this. But I see that you're waffling now; you now say that "I'm not sure what the actual
temperature was".

I said it was 40 years ago! And I make *no* claims about any
absolute accuracy of any specific detail. I'm *not* making a
point of what the specific material was, what the exact
temperature was, what the exact pressure was.

I appreciate corrections to what would obviously have to be the
correct parameters. Clearly at 70 some degrees C cadmium will
out-gas if the pressure is down to 10^-8 Torr.

The point was about apparently solid things simply vaporizing
without being raised to some significantly high temperature,
because *pressure* is just as significant. And the results can
come as an expensive surprise too.

The idea that water boils at 100C and freezes at 0C, without
some mention of pressure, has little meaning. Water can "boil"
at 0C too.

--
Floyd L. Davidson http://web.newsguy.com/floyd_davidson
Ukpeagvik (Barrow, Alaska)