The tale is generally considered to be the first detective story. Auguste Dupin to On April 20, , two teenage gunmen kill 13 people in a shooting spree at Columbine High School in Littleton, Colorado, south of Denver.
At approximately a. Soviet aircraft force a Korean Air Lines passenger jet to land in the Soviet Union after the jet veers into Russian airspace. Two people were killed and several others injured when the jet made a rough landing on a frozen lake about miles south of Murmansk. The jet was on a Colonel Robert E. Lee resigns from the United States army two days after he was offered command of the Union army and three days after his native state, Virginia, seceded from the Union.
Lee opposed secession, but he was a loyal son of Virginia. His official resignation was only Danica Patrick was born on March 25, , in Beloit, Wisconsin.
She became involved in racing as a young girl Live TV. This Day In History. History Vault. Civil Rights Movement. Image explanation. Polonium is an alpha-emitter, and is used as an alpha-particle source in the form of a thin film on a stainless steel disc. These are used in antistatic devices and for research purposes. This makes it useful as a source of heat for space equipment. Biological role. Polonium has no known biological role.
It is highly toxic due to its radioactivity. Natural abundance. Polonium is a very rare natural element. It is found in uranium ores but it is uneconomical to extract it. It is obtained by bombarding bismuth with neutrons to give bismuth, which then decays to form polonium. All the commercially produced polonium in the world is made in Russia. Help text not available for this section currently. Elements and Periodic Table History.
Uranium ores contain minute traces of polonium at levels of parts per billion. Despite this, in Marie Curie and husband Pierre Curie extracted some from pitchblende uranium oxide, U 3 O 8 after months of painstaking work. The existence of this element had been forecast by the Mendeleev who could see from his periodic table that there might well be the element that followed bismuth and he predicted it would have an atomic weight of The Curies had extracted the isotope polonium and which has a half-life of years.
Before the advent of nuclear reactors, the only source of polonium was uranium ore but that did not prevent its being separated and used in anti-static devices. These relied on the alpha particles that polonium emits to neutralise electric charge. 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.
Supply risk. Relative supply risk Unknown Crustal abundance ppm 0. 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 Polonium 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 in Chemistry in its element the story of a substance that was named to snub Russia, power space probes keeps paper static free and has even been used as a murder weapon in London.
To reveal the secrets of Marie Curie's element, and that's polonium, here's Johnny Ball. Polonium, element 84 , was discovered in and named after Poland, the homeland of Marie Curie Ne Sklodowska who found it with her husband Pierre Curie. This loyalty was a direct affront to Russia who had dominated Poland for so long.
The only way she could become educated whilst a teenager, was by risking imprisonment by the Russians by attending secret underground schools, which had to change locations every couple of days. It was only by escaping to Paris, following her older brother and sister, that she was able to forge a career.
She was so poor in the early years in Paris, that she sometimes fainted through lack of food. Still she worked tirelessly. In she met Pierre, who had made a name for himself in discovering piezoelectricity and was one of her lecturers. They married in July She wore a black dress as it would be serviceable for her work in the laboratory.
They did not exchange rings, but bought each other a bicycle, on which they honeymooned. Working with him 98 , Marie coined the phrase "radioactivity" and decided to make this here object of study, because no one else was doing it. They realised that radiation was coming from the very atoms and that this was a sign of the atoms breaking up.
Only by studying the break up of atoms through radiation, were scientists able to clearly understand how atoms are made up. Pierre died in a tragic accident in In driving rain he seemed to walk in front of a large horse-drawn wagon, and a wheel shattered his head. Some think the pain he was in as a result of radiation burns and sickness may have caused his lack of awareness.
Marie was devastated, but her work continued. For discovering polonium and radium, she received the Nobel Prize for Chemistry in , becoming the only woman ever to receive two such prizes. The Curies laboratory notebook has no record from July to 11 November. Second, they found that a radioactive substance could be concentrated by fractional crystallization from barium chloride contained in pitchblende.
They pursued this operation until the activity of the chlorides was times greater than that of uranium. Their third and last argument was decisive. This time the spectroscopic analysis was successful.
Marie Curie maintained a strong sense of ownership for the element [polonium], which she defended with considerable emotion and vehemence. In December , the Austrian government offered the Curies a first batch of kg of uranium-free residue from the treatment of the Joachimsthal pitchblende. The determination of the atomic mass of radium became an obsession for Marie Curie.
With the foregoing discovery of polonium, the Curies had oddly enough begun with the most difficult part of the work. In its own right, radium had outstanding advantages: its half-life is years; its concentration in the ores was about times greater than that of polonium; it is a true analog of barium, from which it can be separated; and it could be readily assigned its place in the periodic table. He was research student of Marguerite Perey who was assistant of Marie Curie and discoverer of francium.
See the References section for works cited in this article. Questions regarding the website, please contact edit. Your documents are now available to view. Confirm Cancel. Accessible Published by De Gruyter January 1, Cite this. Published Online: Published in Print: Adloff, b. A Short History of Polonium and Radium.
With atomic number 88, it has four natural isotopes of atomic weight , , and - though there are a remarkable 21 more artificial isotopes. A later starring role for radium would be as the source of alpha particles - helium nuclei - used by Rutherford in at the Cavendish laboratory in Cambridge to fire at a thin gold foil.
Radium decays to radon, throwing out an alpha particle from its nucleus. Unexpectedly, Rutherford's assistants Hans Geiger and Ernest Marsden found that a very few of the alpha particles bounced back - Rutherford likened it to 'firing a 15 inch shell at a piece of tissue paper and having it come back and hit you.
Radium's main practical use has been in medicine, producing radon gas from radium chloride to be used in radiotherapy for cancer. This was a process started in Marie Curie's time. The early researchers found they received skin burns from handling the radioactive materials, and when the Curies worked with doctors, they discovered that radiation could be used to reduce or even cure tumours.
This became known as Curie therapy, and the Sorbonne in Paris set up a laboratory partly for Curie to continue her research, and partly to study the medical applications of radiation, which would become known as the Radium Institute. If you were to hold a piece of radium in your hand, it would feel warm. Initially a bright white, it would blacken as it reacted with the air to form radium nitride. It would stay solid - radium doesn't melt until around degrees Celsius. It would also crackle and spit on the surface of your palm as it reacted with the water on your skin to produce radium hydroxide.
Holding radium not something I'd recommend, though. Radium is constantly decaying, producing the alpha particles Rutherford used, beta particles, which are fast electrons, and gamma rays, like high energy X-rays, which would be slamming through your flesh, disrupting the DNA and causing cellular damage.
This is an element to be handled with care. Yet for anyone brought up on children's fiction full of ray guns and in a world were there were still X-ray machines to check your shoe size, it has a nostalgic feel that will ever make it fascinating. One wonders whether the podcasters of next century will be talking the same way about mobile phones, microwave ovens and MRI scanners.
That was Bristol based science writer Brian Clegg with the story of radium. Next week to a metal capable of terrible cruelty to cancer. In the early s, Barnett Rosenberg was conducting experiments on bacteria, measuring the effects of electrical currents on cell growth. The E. A number of platinum compounds were being formed due to reaction of the buffer and the platinum electrode. Cisplatin was found to inhibit cell division thus causing the elongation of the bacteria and was tested in was tested in mice for anticancer properties.
Cisplatin today is widely used to treat epithelial malignancies with outstanding results in the treatment of testicular cancers. So we've got overgrown E. And you can find out how all of that came about with Keele University's Katherine Haxton on next week's Chemistry in its element.
I'm Chris Smith, thank you for listening and for this week goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Radium.
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Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium.
K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership.
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