Making heavier plutonium nuclides is just as easy — when Pu captures additional neutrons it turns into Pu, Pu, Pu, and more. Not only is it fairly easy, but it happens all the time in any operating nuclear reactor.
Making the lighter nuclide is a little more roundabout. Remember that, through neutron capture, a reactor produces Pu Am is an alpha emitter and it decays to a lighter variety of neptunium Np which, when subjected to neutron irradiation, captures a neutron to become Np One final transformation — a last beta decay — is the last step to producing Pu This is the reason why Pu is so expensive — making it requires two bouts of irradiation the first long enough to produce the Pu , enough time for all of the radioactive decays to transform plutonium into americium and the americium into neptunium, and several steps of chemical processing to isolate the various elements of interest that are formed.
Although it sounds convoluted well, I guess it is convoluted , making Pu is fairly straight-forward. The science and engineering are both well-known and well-established, and its production certainly breaks no new scientific or technical ground. As I mentioned last week, the American Pu production line shut down over two decades ago. So this option is not going to work for much longer, regardless of the future of US-Russian international relations.
But if there is a Pu stockpile at LANL it would certainly be nice to tap it for space exploration — not to mention the savings in disposal costs.
The availability of suitable substitutes for a given commodity. The percentage of an element produced in the top producing country. The higher the value, the larger risk there is to supply. The percentage of the world reserves located in the country with the largest reserves. A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Specific heat capacity is the amount of energy needed to change the temperature of a kilogram of a substance by 1 K. A measure of the stiffness of a substance. It provides a measure of how difficult it is to extend a material, with a value given by the ratio of tensile strength to tensile strain. A measure of how difficult it is to deform a material. It is given by the ratio of the shear stress to the shear strain. A measure of how difficult it is to compress a substance.
It is given by the ratio of the pressure on a body to the fractional decrease in volume. A measure of the propensity of a substance to evaporate. It is defined as the equilibrium pressure exerted by the gas produced above a substance in a closed system. This Site has been carefully prepared for your visit, and we ask you to honour and agree to the following terms and conditions when using this Site.
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Discovery date Discovered by Glenn Seaborg and colleagues Origin of the name Plutonium, is named after the then planet Pluto, following from the two previous elements uranium and neptunium.
Glossary Group A vertical column in the periodic table. Fact box. Glossary Image explanation Murray Robertson is the artist behind the images which make up Visual Elements. Appearance The description of the element in its natural form. Biological role The role of the element in humans, animals and plants. Natural abundance Where the element is most commonly found in nature, and how it is sourced commercially. Uses and properties. Image explanation. A few people laughed, a few people cried.
Most people were silent. I remembered the line from the Hindu scripture, the Bhagavad-Gita. Plutonium was used in several of the first atomic bombs, and is still used in nuclear weapons. The complete detonation of a kilogram of plutonium produces an explosion equivalent to over 10, tonnes of chemical explosive. Plutonium is also a key material in the development of nuclear power. It has been used as a source of energy on space missions, such as the Mars Curiosity Rover and the New Horizons spacecraft on its way to Pluto.
Biological role. Plutonium has no known biological role. It is extremely toxic due to its radioactivity. Natural abundance. The greatest source of plutonium is the irradiation of uranium in nuclear reactors. This produces the isotope plutonium, which has a half-life of 24, years. Help text not available for this section currently. Elements and Periodic Table History. They produced it by bombarding uranium with deuterium nuclei alpha particles.
This first produced neptunium with a half-life of two days, and this decayed by beta emission to form element 94 plutonium. Within a couple of months element 94 had been conclusively identified and its basic chemistry shown to be like that of uranium. To begin with, the amounts of plutonium produced were invisible to the eye, but by August there was enough to see and weigh, albeit only 3 millionths of a gram.
However, by the Americans had several kilograms, and enough plutonium to make three atomic bombs, one of which exploded over Nagasaki in August Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk.
Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material.
Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Plutonium Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
Hello, this week on Chemistry in its element a substance that most people think is man made but in fact often turns up in the centres of stars.
It also packs a huge nuclear punch when it's in the right sort of warhead and also has the power to be a super conductor. The only problem is its radio active and that means that when it decays it tends to fall apart. Plutonium's often billed as the 'most toxic substance known to man'. Just the word plutonium instils a dread in people's minds - And it's the early history of plutonium that established its dark side - and it's a reputation that's been hard to shake-off since.
Glenn Seaborg discovered plutonium at Berkeley in , and in the following spring, when it was found that it could sustain a nuclear chain reaction, he secretly wrote to President Roosevelt, to inform him of that this substance had the potential to be a powerful source of nuclear energy. And from that moment the race was on to produce significant amounts to supply a secret project codenamed the Manhattan Engineering District, the goal of which was to produce a nuclear bomb.
Anyone familiar with the iconic image of the mushroom cloud understands the tremendous explosive power of a correctly controlled detonation of plutonium. The energy density is mind-boggling: a sphere of metal 10 cm in diameter and weighing just 8 Kg is enough to produce an explosion at least as big as the one that devastated Nagasaki in But apart from military uses like this, plutonium also has one of the richest chemistries of any element.
There are six different forms of plutonium, known as allotropes, that all exist at different temperatures and behave differently. At room temperature, for instance, the plutonium is very brittle, but heated to around Celsius is transforms to a much more malleable metal. Scientists have found that they can mimic this effect by adding a small amount of gallium, which gives the room temperature metal similar properties to its higher-temperature counterpart, and this makes it much easier to work with.
Mixing plutonium with other metals can also produce substances with other interesting properties. For instance, adding some cobalt and gallium can produce a material that behaves as a super-conductor at low temperatures. Its electrons link up into a close-knit arrangement called Cooper pairs, which allow electricity to flow freely with no resistance. But unfortunately this arrangement doesn't last very long.
Because plutonium self destructs, undergoing radioactive decay by spitting out a highly energetic alpha-particle to produce Uranium But as the alpha-particle leaves it causes the uranium nucleus to recoil like a gun that's just been fired, and this damages the structure of the material, disrupting the paired electrons and slowly destroying the superconductivity. So in this sense plutonium is its own worst enemy.
Its radioactivity means that it's very difficult to exploit the richness of its chemistry in many compounds, and as its reputation precedes it, plutonium would also have trouble gaining acceptance as a technological material. Nowadays it's been replaced by better batteries, but it's still popular with space scientists who use it to power probes sent to explore distant planets far from the Sun, like Cassini, that was sent to Saturn, and New Horizons, which is on its way to Pluto.
Plutonium's in a part of the periodic table called the actinide series alongside its neighbours thorium and protoactinium. Seaborg christened the actinides, rearranging the periodic table in the process, on the basis of the unusual arrangements of their electrons, which give these substances unusual magnetic properties, as well as the ability to have multiple oxidation states.
Plutonium, for instance, has five, giving it the ability to form an unusually wide range of compounds that scientists are only just beginning to get to grips with. Some say that plutonium's an evil element created by man, but it's actually a natural element produced by a process known as nucleosynthesis, which takes place in supernova explosions, when dying stars blow themselves to pieces.
There isn't much of it on the earth naturally, because the majority of its isotopes have such short half-lives. And in the 4. What there is mostly comes from reactors and nuclear tests. There are severe hazards associated with plutonium, but as with most dangerous materials, these can be mitigated by careful handling and rigorous safeguards. But whatever you think about plutonium, its history, however chequered, has revealed some fascinating chemistry. Although the mushroom cloud remains its best-known image.
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