Marguerite Perey: When The Lab Assistant Gets The Credit

Most people obtain a bachelor’s degree before getting their masters, and even that is a prerequisite for a doctorate. Most people, however, don’t discover a new chemical element.

Marguerite Perey graduated with a chemistry diploma from Paris’ Technical School of Women’s Education in 1929, and applied for work at the Curie Institute, at the time one of the leading chemistry and physics labs in the world. She was hired, and put to work cataloging and preparing samples of the element actinium. This element had been discovered thirty years before by a chemist who had also been working in the Curie laboratory, but this was the height of the chemical revolution and the studies and research must continue.

When Marie Curie died in 1934, the discoverer of actinium, André-Louis Debierne, continued his research and Perey kept providing samples. Marguerite’s work was recognized, and in time she was promoted from a simple lab assistant to a  radiochemist. It would not be an exaggeration to say that Marguerite was, at the time, the world’s leading expert in the preparation of actinium. This expertise would lead her to the discovery of the bottom left corner of the periodic table: francium, element 87, the least electronegative element, and arguably the most difficult naturally occurring element to isolate.

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7th Period of the Periodic Table Complete

For the last fifty or so years, the periodic table has been incomplete. Elements after uranium on the periodic table have been synthesized for the past few decades, but there were always a few missing blocks in the periodic table. These elements, with atomic numbers of 113, 115, 117, and 118 comprise the missing parts of period 7 – the lowest row – of the periodic table. Now, IUPAC, the International Union of Pure and Applied Chemistry, has announced the verification of the discoveries of the last four elements of the seventh period of the periodic table.

With the announcement of the verification of discovery for these elements, they will get a name. Currently elements 113, 115, 117, and 118 are known as Ununtrium, Ununpentium, Ununseptium, and Ununoctium, respectively. What these elements will be named depends on the proposals by the discoverers of these elements.

Element 113 was discovered by researchers at the RIKEN laboratory in Japan, and these researchers will be able to propose a name and atomic symbol for their discovery. Elements 115, 117, and 118 were discovered through a partnership between the Joint Institute for Nuclear Research in Dubna, Russia, Lawrence Livermore National Laboratory in California, and Oak Ridge National Laboratory in Oak Ridge, Tennessee. Researchers at these three laboratories will propose names and atomic symbols for these three elements.

It should be noted that Lawrence Livermore National Laboratories and the Joint Institute for Nuclear Research in Dubna each have their own element named after them: Lawrencium and Dubnium, with atomic numbers 103 and 105, respectively. Having element 113, 115, and 118 named after Oak Ridge National Laboratory wouldn’t be a bad proposal, and would be rather fitting given the laboratory’s influence on the last half-century of physics.

Of particular interest is the naming of element 118. Because element 118 falls within group 18 of the periodic table, it is a noble gas, with a particular naming pattern. each of the elements in group 18 end with the suffix ~on, instead of the suffix for the rest of the periodic table, ~ium (helium is the exception to this rule due to historical precedent). Whether element 118 will use the ~on or ~ium suffix is up to debate; current IUPAC rules say all new elements should end with ~ium, but recommendations have been published to name all group 18 elements with the ~on suffix.

This is not the end of the periodic table by any means. It is possible that elements with higher atomic numbers can be synthesized. However, experiments to synthesize element 119 have so far come up short, and the predicted properties of element 119 put it at the limits of what current technology is able to detect.

Don’t Understand the Periodic Table? It’s Just a Quantum Truth Table

In the wee hours of the late 17th century, Isaac Newton could be found locked up in his laboratory prodding the secrets of nature. Giant plumes of green smoke poured from cauldrons of all shapes and sizes, while others hissed  and spat new and mysterious chemical concoctions, like miniature volcanoes erupting with knowledge from the unknown. Under the eerie glow of twinkling candle light, Newton would go on to write over a million words on the subject of alchemy. He had to do so in secret because the practice was frowned upon at that time.  In fact, it is now known that alchemy was the ‘science’ in which he was chiefly interested in. His fascination with turning lead into gold via the elusive philosopher’s stone is now evident. He had even turned down a professorship at Cambridge and instead opted for England’s Director of Mint, where he oversaw his nation’s gold repository.

Not much was known about the fundamental structure of matter in Newton’s time. The first version of the periodic table would not come along for more than a hundred and forty years after his death. With the modern atomic structure not surfacing for another 30 years after that. Today, we know that we can’t turn lead into gold without setting the world on fire. Alchemy is recognized as a pseudoscience, and we opt for modern chemistry to describe the interactions between the elements. Everyone walking out of high school knows what atoms and the periodic table are. They know what the sub-atomic particles and their associated electric charges are. In this article, we’re going to push beyond the basics. We’re going to look at atomic structure from a quantum mechanical view, which will give you a new understanding of why the periodic table looks the way it does. In fact, you can construct the entire periodic table using nothing but the quantum numbers.

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Elemental display is also a LED wall


[Dan] is an element collector, someone who gets his socks knocked off by bismuth crystals and the orange vapor of bromine. Of course every element collector needs a proper display case, and since the periodic table table idea is cliché, [Dan] decided to build an elemental display that’s also a really awesome LED wall.

The build started off as most do with a few sheets of plywood and 120 acrylic shelves for each item in [Dan]’s collection. The real magic happened when [Dan]’s buddy [Bill] was called in to make the display a little more interesting.

Behind each acrylic shelf is a three-LED section of a LED strip, each part of the periodic table having a different color. The 120 individual shelving units are broken down into 16-shelf groups, each driven by a custom LED driver board. These driver boards are connected to a master Arduino with phone cables and make wonderful use of a very neat TCL5940 Arduino library.

The elemental display has a few options; all-on, twinkling, an Apple ‘breathing’ mode, and a graphic eq, as shown in the video after the break.

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