Name: Named for the Americas, where it was discovered.
Atomic mass: (243).
History: Americium was the fourth transuranic element to be discovered. The isotope Am-241 was identified by Glenn T. Seaborg, Ralph A. James, Leon O. (Tom) Morgan, and Albert Ghiorso late in 1944 at the University of Chicago's wartime Metallurgical Laboratory (now Argonne National Lab).
Occurrence: Does not occur naturally.
Appearance: White solid metal, more silvery than plutonium or neptunium, prepared in the same manner.
Behavior: Tarnishes slowly in dry air. Highly dangerous because of its intense a-radiation.
Uses: Americium-241 is made in large quantities in nuclear reactors and is available to qualified users in the U.S. and the U.K. It is used as a portable source of X-rays, as a source of ionization for smoke detectors, and as a radioactive glass thickness gauge for the flat-glass industry.
I enjoy watching trivia game shows such as "Jeopardy!" and "Win Ben Stein's Money." Sure, I like to see how I stack up against the contestants, but what I really enjoy are the interesting tidbits of information you can gather.

Now imagine my glee had I been alive in 1945 and listening to the radio. I would have picked up one of the best tidbits ever.

"Quiz Kids" was a live radio game show produced from 1940 to 1953 by NBC that featured children with high IQs, including future Nobelist James D. Watson. On Nov. 11, 1945, Glenn T. Seaborg appeared as a guest on "Quiz Kids." One of the children on the show, Richard Williams, asked Seaborg if any new elements, in addition to plutonium and neptunium, had been discovered at the Metallurgical Laboratory in Chicago during the war. Since the discovery information had already been declassified for announcement at the forthcoming ACS national meeting on Nov. 16, Seaborg shared the news that two new elements with atomic numbers 95 and 96 had been discovered.

It's not every day that you hear about new elements announced on a game show. Talk about a golden nugget of a tidbit.

Seaborg then told Williams, "So now you'll have to tell your teachers to change the 92 elements in your schoolbook to 96 elements." Seaborg later recalled in his 1979 Priestley Medal address that many kids did, in fact, tell their teachers to change the number of elements. "Judging from some of the letters I received from such youngsters, they were not entirely successful in convincing their teachers," he said.

Initially, Seaborg's group had difficulty chemically separating the two new elements from the rare-earth elements. One of the members of the group, Tom Morgan, dubbed the two elements "pandemonium" and "delirium." Morgan's nicknames encompass the frustration of the group during their attempts to demonstrate the chemical proof of the elements' existence.

Element 95 made one more radio appearance before receiving its formal name. On Dec. 15, 1945, Seaborg was a guest on the radio program "Adventures in Science." The announcer of the program wanted to know if elements 95 and 96 had been named. Seaborg replied that "naming one of the fundamental substances of the universe is, of course, something that should be done only after careful thought."

The announcer then suggested that listeners of the program might be interested in submitting name suggestions for the new elements. Listeners were advised to send a postcard to the program, and in return, they received a free issue of Chemistry magazine that included Seaborg's technical paper and revised periodic table.

Seaborg later sent a response to "Adventures in Science" sharing the names that people had suggested. Since all of the planets' names had already been used, some listeners suggested other astronomical bodies such as "big dipperain" and "sunonium." Other listeners suggested "artifium," "artifician," "cyclo" (after the cyclotron), and "mechanicium," since element 95 had been created in a lab and did not occur naturally. Interestingly, one listener suggested element 95 be named "curium" and element 96 "einsteinium." Those suggested names were eventually applied to elements 96 and 99, respectively, so some good ideas did come from the radio solicitation.

SPILT BEANS Quiz Kids Sheila Conlan (center) and Bob Burke (right) with Seaborg the day he informally announced elements 95 and 96 on the radio show.
In the end, element 95 was named "americium" because of its position in the periodic table. Since its lanthanide homolog, europium, was named after Europe, Seaborg felt it appropriate for element 95 to be named after the Americas.

And now for one last tidbit of information. Americium was introduced into many homes via the radio. Today, however, the radioactive element can physically be found in almost every home and saves countless lives every year.

Have you figured out where it hides yet? No fair cheating with the information box on this page!

How about your smoke detector? Small amounts of americium are used as ionization sources in smoke detectors. The americium emits -particles that ionize the surrounding air, increasing electrical conductivity. When smoke enters the ionization chamber, it disrupts the electrical conductivity and triggers the alarm.

With so many interesting tidbits of information, americium would make a great quiz show category. Should I ever actually end up on a quiz show, I'll certainly be hoping I get to say, "I'll take 'americium' for $200, please!"

Rachel Sheremeta Pepling is an assistant editor for C&EN Online. She oversees the feature "Critter Chemistry."

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