HOT STUFF about technetium and radium from a guy who knows his stuff

On 15 Jul 2005, at 14:23, Robert Merkin wrote:

Dear Professor Marshall,

Please excuse dumb questions from total stranger and not great chemistry/physics student.

My wife and I have bumbled into technetium. The silly story of how we bumbled onto technetium is on my blog at

http://vleeptron.blogspot.com/2005/07/can-sherlock-holmes-or-miss-marple-or.html

Your sample on http://www.webelements.com/webelements/elements/text/Tc/key.html
says

There is a thin plating of technetium-99 on this disk and this radioactive sample gives about 200 counts per minute.

The webelements radium page doesn't give a comparable "count." If this is a meaningful or well-defined question, what would the "count" be for a comparable mass of radium? How "hot" are these two elements comparatively?

Thanks for helping us with our curiosity.

Bob Merkin
Northampton Massachusetts USA

*******

Dr. Jim Marshall
Department of Chemistry
University of North Texas
Denton, Texas
http://www.jennymarshall.com/rediscovery.htm
Email jimm@unt.edu

Hi, good to hear from you.

200 counts per minute is so incredibly below the danger horizon! If you had a gram of radium, you would have over a TRILLION [ 1,000,000,000,000 ] counts per minute! THe sample would be hot and would glow!

Furthermore, radium is DANGEROUS because it is in the calcium family of the periodic table and replaces the atoms in your bones, causing them to crumble. Technetium, on the other hand, is chemically innocuous (they use it in the body for tracer studies!) . . . . .

Now, I have some radium clocks, dating from the first half of the twentieth century (you can find them occasionally in antique shops) which have a count of, give or take, 200-400 counts per minute, in other words, about the same as the technetium sample. Since the half life of radium and technetium are comparable (a thousand years or so), then this is a meaningful comparison: The radium of a radium clocks is a very dilute layer of radium salts mixed with barium sulfate. The working girls who painted the hands and numbers of the radium clocks frequently ingested
the paint, causing cancer.

Hope this helps, so long for now . . . .

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Oh yeah when I was a kid I went off to summer camp with a new radium dial wristwatch my grandfather gave me. It was real nifty. I spent every summer night under the blanket with the wristwatch glued to my eye to look at the glow-in-the-dark numbers and hands. (Radioactivity is a statistics and probability thing -- a Luck Thing, that sometimes protects Idiots and their Grandfathers.)

The women radium watch and clock painters would put the tiny brushes in their mouths to lick them to a fine point.

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From "Science in Poland": http://www.staff.amu.edu.pl/~zbzw/ph/sci/msc.htm

Maria Sklodowska (born Warsaw, Poland 7 November 1867) was ... the fifth and youngest child of Bronsilawa Boguska, a pianist, singer, and teacher, and Wladyslaw Sklodowski, a professor of mathematics and physics.

... While (her husband) Pierre Curie devoted himself chiefly to the physical study of the new radiations, Maria Curie struggled to obtain pure radium in the metallic state -- achieved with the help of the chemist A. Debierne, one of Pierre Curie's pupils. On the results of this research Maria Curie received her doctorate of science in June 1903 and, with Pierre, was awarded the Davy Medal of the Royal Society. Also in 1903 they shared with Becquerel the Nobel Prize for Physics for the discovery of radioactivity ...

... On May 13, 1906, she was appointed to the professorship that had been left vacant on her husband's death; she was the first woman to teach in the Sorbonne. In 1908 she became titular professor, and in 1910 her fundamental treatise on radioactivity was published. In 1911 she was awarded the Nobel Prize for Chemistry, for the isolation of pure radium ...

In 1921, accompanied by her two daughters, Maria Curie made a triumphant journey to the United States, where President Warren G. Harding presented her with a gram of radium bought as the result of a collection among American women. She gave lectures, especially in Belgium, Brazil, Spain, and Czechoslovakia. She was made a member of the International Commission on Intellectual Co-operation by the Council of the League of Nations. In addition, she had the satisfaction of seeing the Curie Foundation in Paris develop and the inauguration in 1932 in Warsaw of the Radium Institute, of which her sister Bronia became director.

On July 4, 1934, near Sallanches (France), Maria Sklodowska-Curie died of leukæmia, which has a number of standard consequences, one of which can be aplastic anæmia caused by her exposure to the radium that made her famous.

Recognizing Maria Sklodowska-Curie with perhaps its highest posthumous honor in 1995, the French Government transferred her ashes, together with those of Pierre, to the Panthéon in Paris, making her the only woman (she is the first woman, again) to be recognized in this way for her own achievements.