June 9, 2011

Periodic Table Gets Bigger, 2 New Elements Added

Scientists from the scientific governing committees of physics and chemistry have added two new elements -- yet to be named -- to the periodic table, reports The Associated Press (AP).

The elements, currently known only as 114 and 116, are both highly radioactive and, with respective atomic weights of 289 and 292, are now the heaviest elements on the periodic table of elements, bumping copernicium and roentgenium down the list of heavyweights.

The two radioactive elements exist only for a fraction of a second before decaying into lighter atoms. While the new elements have yet to be officially named, they have been temporarily dubbed ununquadium and ununhexium.

The discovery of the elements has been credited to the Joint Institute for Nuclear Research in Dubna, Russia and Lawrence Livermore National Laboratory in California.

Chemist Ken Moody of the Lawrence Livermore National Laboratory, who was part of the discovery team, said he hasn't talked to his colleagues about what element names to propose to an international group of scientists for approval. But he does know the names will have to end in "ium."

However, a Huffington Post news source reported that the collaborative group had come up with proposed names for the two elements. The proposed name for element 114 is flerovium -- after Soviet scientist Georgy Flyorov. Element 116 has the proposed name moscovium -- for the Moscow region in Russia.

The review was conducted by a joint working party of the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP). The process of approval could take as long as three years.

The two new elements bring the total number of known elements to 114, because 113, 115 and 118 are still pending approval, according to Paul Karol of Carnegie Mellon University.

Karol chaired the committee that recognized the new elements, based on experiments done in 2004 and 2006 by the joint collaborators from Russia and California.

New elements are added to the table about once every 2.5 years, said Karol, adding that the list has been continually updated over the past 250 years.

The new elements were created by slamming two lighter elements together in the hopes that they would stick, said Karol. The numbers of the elements refer to the number of protons in the nucleus.

"It's one atom at a time," he told BBC News on Wednesday. The elements exist for less than one second before falling apart, so the total accumulation is "a sprinkling," he said.

Making new elements is just a byproduct of an effort to discover things about the atomic nucleus, Moody said. "It's just basic science "¦ and kind of fun," he said.

Moody, 56, said that when he was in high school there were only 104 elements on the table. At that time chemists believed the list was about finished. He said he recently spoke about his work to some high school students and found them to be fascinated by it.

To them the periodic table "is an icon," he said. "The fact that it can change and it can be added to, I think, is a novel idea for younger people."

Details of the new element research have been published in the journal Pure and Applied Chemistry. 


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