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Meet 115, the Newest Element on the Periodic Table The extremely heavy element was just confirmed by scientists in Sweden

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Meet 115, the Newest Element on the Periodic Table

The extremely heavy element was just confirmed by scientists in Sweden.

Melody Kramer

for National Geographic


If you've learned all the elements from actinium to zirconium, it's time to head back to the periodic table, where there's a new, extremely heavy element in town.

The new element doesn't have an official name yet, so scientists are calling it ununpentium, based on the Latin and Greek words for its atomic number, 115.   In case you forgot your high school chemistry, here's a quick refresher: An element's atomic number is the number of protons it contains in its nucleus.

The heaviest element in nature is uranium, which has 92 protons. But heavier elements-which have more protons in their nucleus-can be created through nuclear fusion.

The man-made 115 was first created by Russian scientists in Dubna about ten years ago. This week, chemists at Lund University in Sweden announced that they had replicated the Russian study at the GSI Helmholtz Center for Heavy Ion Research in Germany.

Element 115 will join its neighbors 114 and 116-flerovium and livermorium, respectively-on the periodic table just as soon as a committee from the International Union of Pure and Applied Chemistry(IUPAC) decides on an official name for 115.

We asked Paul Hooker, a chemistry professor at Westminster College in Salt Lake City, Utah, for his take on the latest addition to the periodic table.

So it sounds like 115 was actually created ten years ago, by a lab in Russia. Why are we just learning about its discovery?

When you find a new element, it has to be confirmed. You need two different labs to confirm it before [IUPAC] considers adding it to the periodic table.

This is the second lab coming in and repeating the same experiment, so now it's considered to be an official new element.

So what did the Russian and Swedish chemists actually do?

The way that you make new elements now is by shooting a beam of an element at another element and then seeing what happens when they collide.

In this case, the researchers used americium, which is kind of interesting because it's an unstable, radioactive element. They fired calcium atoms-which are much lighter than americium atoms-at the americium for weeks or even months. Most of the calcium atoms bounced off, but every now and then the atoms collided and instead of the calcium element bouncing off, it actually stuck to the americium element. When that happens, you get a short-lived atom with more protons in its nucleus, which is the center of the new element 115.

How did they know they created a new element if it happened so quickly? I think I read that it existed for less than a second before it decayed.

They look for the decay products. They look for telltale signs for when 115 disintegrates, by what's called alpha particle emission. When they see enough of those signals, they can say they probably formed a new element.

How do they know if a new element will be unstable or not?

There was an element 118 that was predicted to be much more stable; 115 wasn't predicted to be especially stable. We know what is stable. Certain ratios of protons to neutrons are stable. As the nucleus gets bigger and bigger, it's not stable-and then it can radioactively decay and spit out smaller particles-that means it's really not very stable.

Can anyone try to create a new element?

No. You need a large vacuum chamber because you can't fire calcium atoms through the air. You need a lot of specialized equipment. There aren't many labs that can do this type of thing. The only people interested in doing this are trying to answer some of the bigger questions, like "How is all matter held together?"

Where are most new elements created?

Most of these new elements have been formed in Russia and the States for the past 30 to 40 years. It's become a race for who can get the next new element, to try to make the biggest one you actually can. But of course, because they're so big, they're very unstable and fall apart extremely quickly.

If they fall apart extremely quickly-and clearly don't exist in nature-then what's the point?

I talk about this a lot with my students. I basically tell them, "Because it's there." There's no way that a new, unstable element is going to have any uses because it deteriorates so quickly. But it gives insight about the forces that hold atoms together so we can learn more about how the universe is held together.

Why are people really doing this? Why do we send particles through huge colliders? Why are we smashing things into each other at higher and higher velocities? I think it fulfills the human race's natural curiosity. We want to know where we come from. And every time we answer something, we come up with ten more questions to answer.

This was a man-made element. How do we know we've found all of the naturally occurring elements?

The good thing with elements is that they're defined by atomic numbers, meaning they're defined by the number of protons in the nucleus. This number is never a fraction, so you can't have, say, 3.2 protons in a nucleus. So we know we have them all because we know of an element with one proton and an element with two protons and so on.

Is there a limit to how many elements we can create?

Well, we're hitting a limit with stability when there are over 90 protons in a nucleus, so while we may find more, we're certainly not getting up to 1,000 protons. It would be too unstable.

One last question: I actually have a periodic table shower curtain. Do you recommend getting an updated one?

I recommend updating your shower curtain when 115 is confirmed. When the committee gets together and names it. And that's an entirely different question.

So I guess I should ask: Why does a committee do it?

Because these things get quite political. Back in the day, the Americans would say: We discovered it and named it something. The Russians would say: We did, and named it something else. So a committee has to get together and negotiate. They try to keep it apolitical-maybe they'll name it after someone from Italy or Lithuania or something.

Comprehension Questions

  1. Elements on the periodic table are defined by their atomic number. Citing evidence from the article, explain what this means in your own words. ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

  2. Citing evidence from the article and from the periodic table, what can you assume about the weight of this new element in comparison to most other elements?


  1. Citing evidence from the article, where did the name of this new super-heavy element come from?


The periodic table is getting a new addition - say hello to element 117: ununseptium

JAMES VINCENT Tuesday 06 May 2014

The 'superheavy' element existed for only a fraction of a second - but it takes scientists one step closer to the periodic table's theorised 'island of stability'

The periodic table of elements is one step closer to welcoming a new addition to its ranks after scientists independently confirmed the existence of a highly radioactive 117th element.

An international team working at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, were able to create four atoms of ununseptium (the name is a Latin placeholder meaning ‘117’ - a more official title will come later) four years after the element was first spotted by US and Russian researchers.

Like other superheavy elements that populate the tail end of the periodic table, ununseptium only exists for fractions of a second before decaying into other elements.

Scientists hope that its creation is the latest step towards the discovery of the so-called ‘island of stability’ – a predicted group of massive but stable atoms expected to appear somewhere around atomic number 120 onwards.

An atomic number counts the protons within the nucleus of an atom which - along with neutrons - make up the vast majority of an atom’s weight (they’re both around 1800 times more massive than electrons). Like electrons these particles are divided into different shells or levels of atomic energy that predict the element’s stability.

Certain ‘magic numbers’ of protons or neutrons are known to be particularly hardy, and some scientists have predicted that once they make it through the volatile numbers (such as 117) then elements located within the ‘island of stability’ could have half-lives of millions of years - a quality that is not unusual in itself, but that opens up a range of never-before-seen applications when applied to larger elements.

By comparison, ununseptium existed for less than a tenth of a second in the Helmholtz particle accelerator before decaying into a mass of different elements including dubnium (atomic number 105) and lawrencium (atomic number 103).

The team from the GSI Helmholtz Centre led by Christoph Düllmann were actually trying to create element 119 at the time by using a particle accelerator to fire titanium atoms (atomic number 22) at berkelium (atomic number 97).

Transuranium atoms (those with an atomic number greater than uranium’s 92) rarely if ever occur in nature, and have to be artificially created by smashing together lighter elements with the correct atomic numbers.

This heavy-handed style of atomic adding up might sound simple but such experiments are extremely hard to replicate, not least because of the rarity of the target material.

Berkelium, for example, is produced in only very small amounts as a by-product of nuclear reactors and has a half-life of 330 days, giving scientists a limited time frame to use it in experiments. Just 13 milligrams of the highly purified material were used in the creation of ununseptium.

The paper detailing the experiment will be published in the journal Physics Review Letters before being reviewed by the International Union of Pure and Applied Chemistry (IUPAC) – the body responsible for ordering and naming the elements of the periodic table.

If they give the thumbs-up then ununseptium will become an official element - a small but significant addition the general store of human knowledge that quietly makes chemistry textbooks across the world out of date.

Comprehension Questions

  1. The author of the article discusses the “island of stability” that atomic scientists are attempting to create. Citing evidence from the article, explain what “island of stability” means in your own words.


  1. Citing evidence from the article, explain why super heavy elements like ununseptium only exist for less than a tenth of a second.


  1. All atoms have electrons. How much of a role do they electrons play in the overall mass of the atom? Cite evidence from the article in your answer.


14 November 2013 Last updated at 09:08

The periodic table: how elements get their names

By Christopher Brooks BBC Scotland

Most people could name many of the elements, but how many of us know how they got those names?

Each of the 115 known chemical elements was discovered over the last few thousand years, from before recorded history began to the nuclear laboratories of the 21st century.

British scientists and the elements

  • Humphry Davy discovered nine elements using electrolysis - the splitting up of compounds into elements by applying electricity.

  • William Ramsay discovered a new group of unreactive elements using spectroscopy, now called the noble gases.

  • William Crookes identified helium for the first time, and also discovered thallium.

Their chosen names were influenced by an ever changing mix of language, culture and our understanding of chemistry.

So how did they get these names? And why do they end in -ium?

Ancient Elements

Several elements' names have Anglo-Saxon language origins, including gold, iron, copper and silver.

These metals were known long before they got these names, however. Gold can be found in its pure form in nature and although iron is usually found in ores which require smelting, the earliest known iron artefacts, from 3500 BCE, derive from purer metal from meteorites.

The Latin names of these elements are commemorated in their atomic symbols, Au (aurum) for gold and Fe (ferrum) for iron.

The Romans began the practise of element names ending in "-um," with Victorian scientists continuing the trend.

Element of uncertainty

Since 1947, the International Union of Pure and Applied Chemistry (IUPAC) has had the responsibility for approving elements' names, and deciding the single internationally recognised symbol for each element.

Before this, there were multiple historical occasions of elements being given several names, usually due to simultaneous discovery or uncertainty over a discovery.

The name of element 41 was not agreed for 150 years. It was called columbium in America and niobium in Europe until IUPAC finally decided the official name would be niobium in 1949.

Dr Fabienne Meyers, Associate Director of IUPAC, explains the current naming process: To start with, "the discoverers are invited to propose a name and a symbol."

"For linguistic consistency, the recommended practice is that all new elements should end in '-ium'," she adds.

“Start Quote

"Since the sake of naming an element is essentially to avoid confusion, it is important to ensure that the proposed name is unique and has not been used earlier even unofficially or temporarily for a different element."

"After examination and acceptance by the division - which includes a public review period of five months - the name and symbol are then submitted to the IUPAC Council for approval."

The name is then published in the scientific journal Pure and Applied Chemistry.

Actinium to zirconium

A common source of names both now and historically, over a quarter of the elements are named after a place, often where they were discovered or synthesised.

These places range in size from continents (europium) and countries (americium, francium, polonium) to the the Scottish village Strontian (strontium).

Because of the great wealth of discoveries made there, four elements are named after the Swedish mining village, Ytterby (ytterbium, yttrium, erbium and terbium).

There is just one element that wasn't first discovered on Earth, and it too is named after its place of the discovery - helium, from the Greek word for Sun, helios.

Myth and legend

About a dozen elements take their name directly from legends, including titanium, arsenic and tantalum.

Nickel and cobalt are named after 'devil' and 'kobold', from the Germanic folk belief that malign creatures snuck into mines to replace valuable and similar-looking copper and silver ores with these less valuable ones.

In 1949 the artificial element Promethium was named after Prometheus, the man in Greek legend punished with eternal torture for stealing fire from the gods, as a reference to the great difficulty and sacrifice needed to synthesise new elements.

Eponymous elements

Modestly, no discoverer has ever named an element after him or herself, but several scientists have been honoured by having elements named after them. These include curium, einsteinium and fermium.

Seaborgium, named after American chemist Glenn Seaborg, was the first element to be named after a living scientist.

There is also mendelevium, named after Dmitri Mendeleev, the Russian scientist who established the first periodic table in 1869, and fitted the known elements into their places in the table based on their properties.

Elemental techniques

Fifty elements were discovered in the 19th Century, the greatest number of any century. By comparison, twenty nine elements were discovered in the 20th Century, and five new ones have been synthesised so far in the 21st.

Frank James, Professor of the History of Science at The Royal Institution in London, where several elements were discovered, says that the contribution of British scientists was very important.

"Using electro-chemical methods, Humphry Davy either isolated or demonstrated the elemental nature of a total of nine chemical elements naming most of them in the process, such as sodium, potassium and chlorine."

British scientist William Ramsay used a powerful new technique, spectroscopy, to discover the noble gases, a group of elements which had evaded discovery due to their lack of reactivity. He used Greek words to name neon (new), xenon (stranger), krypton (hidden), and argon (inactive).

Colours and sense

Colours are a name source for nine elements. Each element can be identified by the colours it emits using spectroscopy, and several elements are named after the brightest colour they emit, including indium and rubidium.

Visible traits are a major source of names, but the other senses are represented too: osmium and bromine are named for their smell, and aluminium is named after the Latin word for the bitter tasting chemical in which it was first discovered, alum.

Ununpentium onwards

The newest element to be experimentally confirmed, element 115, will be called ununpentium until an official name is decided, and 114 (Flerovium) and 116 (Livermorium) were named in 2012.

IUPAC's Dr Meyers explains that although all recent elements have been named after people and places, "a mythological concept or character, a mineral or a property of the element could also be used as the root for an acceptable name."

And with no shortage of eminent scientists and important centres of science as inspiration, new names will always retain an element of surprise.

Comprehension Questions

  1. Citing evidence from the article, why do some elements have chemical symbols that do not seem to match up with their name? Example: Gold has the chemical symbol ‘Au’


  1. What organization has had the responsibility to approve the name of an element since 1947?


  1. More than 25% of the elements get their names from what?


  1. Citing evidence from the article, why has a person that discovered an element never named it after himself?


  1. What was the first element to be named after a living scientist? ________________________________

  2. How many elements have been discovered in the 21st century? Explain, citing evidence from the article, why you think this number is so low in comparison to other centuries.


  1. What two elements are named after the way they smell? _____________________________________

  2. I
    115 atomic number

    _______ chemical symbol

    __________________ element name

    288 atomic mass

    f you could rename element 115, ununpentium, what name would you give it and why? Fill in the tile

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