Where is americium commonly used




















On this page: Americium in the environment Americium sources Americium and health. Americium in the Environment Am found in the environment is in the form of microscopic dust. When released into air, americium deposits particles in the soil and water. Small particles in air can travel far from the release site. In water, americium will stick to particles in the water or to the sediment at the bottom.

Deposited on soil, americium will stick to surface particles, but not go very deep into the ground. Plants and vegetation growing in or nearby contaminated soil may take up small amounts of americium from the soil. Americium Sources. Contact Us to ask a question, provide feedback, or report a problem. 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. Americium is a silvery, shiny radioactive metal. Americium is commonly used in smoke alarms, but has few other uses.

It has the potential to be used in spacecraft batteries in the future. Currently plutonium is used but availability is poor so alternatives are being considered. Biological role. Americium has no known biological role. It is toxic due to its radioactivity. Natural abundance. Americium occurs naturally in uranium minerals, but only in trace amounts. The main source of the element is the neutron bombardment of plutonium in nuclear reactors.

A few grams are produced in this way each year. Help text not available for this section currently. Elements and Periodic Table History. This element was in fact discovered after curium, the element which follows it in the periodic table. However, it did once exist on Earth having been produced for millions of years in natural nuclear reactors in Oklo, Gabon.

These ceased to function a billion years ago, and as the longest lived isotope is americium, with a half-life of years, none has survived to the present day. The americium was produced by bombarding plutonium with neutrons in a nuclear reactor. This produced isotope americium, which has a half-life of this is years. 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 Americium Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. Elementary envy tops the bill this week with a substance that was christened to compete with Europium.

It was announced to the world via the slightly unorthodox route of a kids' radio show, but this stuff is none the less worth its weight in gold, in fact its worth more than that, 60 times as much in fact, because its gone on to save thousands of lives and homes around the world since.

And to tell us how here's Brian Clegg:. Keeping up with the neighbours is rarely a concern in the periodic table. Nitrogen doesn't care much what carbon and oxygen are up to, and rarely casts covetous glances at phosphorous. But there's at least one substance in the periodic table that was named in response to a nearby element, and that's americium, the element that looks as if it should be pronounced [AMER-ICK-IUM]. It sits in the seventh position in the actinides, those mostly artificial substances that inhabit the second of the periodic table's floating bars of elements, and directly above it, in the parallel list of lanthanides, you will find europium.

Americium's name, according to its discoverers, is 'suggested on the basis of its position. However it was dreamed up, it's an improvement on the provisional names given to americium and curium discovered at the same time - originally they were pandemonium and delirium.

Americium didn't exist until Glen T. Seaborg and his colleagues, working on the Manhattan Project in the Metallurgical Laboratory at the University of Chicago, produced it in It feels strange to say that Seaborg took out a patent on this 'element 95'.

Seaborg's team would isolate a total of 10 new elements, re-arranging the structure of the periodic table. The first hint the world had of the existence of americium came not in a paper for a distinguished journal, but on a children's radio quiz in Seaborg appeared as a guest on NBC's Quiz Kids show, where one of the participants asked him if they had produced any other new elements as well as plutonium and neptunium.

As Seaborg was due to formally announce the discovery of americium five days later, he let slip its existence, along with element 96, later called curium. The first isotope of americium produced was americium , still the most commonly used form.

The Manhattan Project was busy creating plutonium to be used in nuclear weapons, and some plutonium went through a process of capturing extra neutrons to become and then , which gave off an electron from the nucleus to turn into americium.

None of americium's isotopes are truly stable - the longest lasting, americium, has a half-life of years, while many of the 18 isotopes produced only hang around for minutes. Like many of the actinides, Americium is silver-white in appearance, and reasonably heavy with a density similar to that of lead. It's a solid at room temperature - you'd need to heat it to over 1, degrees Celsius to melt it.

But americium has one unique quality. It's the only artificial element - and the only radioisotope - that is routinely found in the home. Actually, I ought to qualify that. We all have traces of natural radioactive elements in our houses. If you live somewhere like Cornwall with a high preponderance of granite, you will have more than your fair share, for instance, of radon about the place, giving a background radiation level of three times that experienced in London.

But americium is the only radioisotope you are likely to go down to the supermarket and buy - what's more, you will have been encouraged to do so by the government. That's because americium is used in many smoke detectors. A tiny quantity - less than a millionth of a gram - of americium oxide will be sitting in there, beaming out radiation as it slowly transforms to neptunium with a half life of years. The alpha particles flowing from the americium it's a better alpha source than radium pass through a small compartment where they ionize the air, allowing a tiny electrical current to cross the chamber.

If smoke particles get in there, they absorb the alpha particles before they can create ions, stopping the current flowing and setting off the alarm.

Every now and then someone will panic when they discover that not only is there a radioactive material in household smoke detectors, but it could, in principle, be used to produce a nuclear weapon.

Assemble enough of that americium and it would go critical. But before any terrorist groups try to corner the market in smoke detectors it's worth pointing out that it would take around billion of them to have sufficient americium assembled to go critical - and even then it wouldn't be enough to put the detectors together in the same place, you would have to painstakingly extract each of those billion specks of the element and mould them together, an effort that would take thousands of years.

Americium has also found other uses for its radioactive emissions, as a source of both alpha particles and gamma rays for medical applications and in industry - but its use is limited to jobs where only a small quantity is required, as it is expensive to produce. The radiation from exposure to americium is the primary cause of health effects from absorbed americium. Americium moves rapidly through the body after uptake and is concentrated within the bones for a long period of time.

During this storage americium will slowly decay and release radioactive particles and rays. These rays can cause alteration of genetic materials and bone cancers. Damage to organs due to americium exposure is highly unlikely for humans, because americium is accumulated in organs only a short period of time. Americium consists mainly of manmade radioactive isotopes. These may be present in soils and waters in very small amounts as a result of atmospheric nuclear weapons testing prior to the nuclear test ban of Americium from atmospheric nuclear weapons tests may remain in the atmosphere for decades travelling all around the world and settling slowly to earth.

Its isotopes decay very slowly in the environment and as a result they can do harm to plants and animals. When animals are exposed to extreme levels of americium, results may be damage to organs such as the lungs, liver and thyroid. Americium that is present in soils may end up in plants, but only in small amounts.

Usually americium particles are stored in parts of the plant that animals will not eat. Within fish very little americium builds up in the flesh or other edible parts and as a result it will not accumulate within food chains. Back to chart periodic elements.



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