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 9. Russia 3 USA Political stability of top producer 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 Yttrium Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. This week, the last of the elements discovered in the small town of Ytterby and its compounds appear to have a multitude of uses. Until about 20 years ago, most scientists had not heard of it, other than vaguely noting where it was in the periodic table, under scandium and above lanthanum.
Some people might just have known that it was one of 4 chemical elements named after the small Swedish town of Ytterby, along with ytterbium, erbium and terbium. Prompting other scientists to dust off their Periodic Tables, and try switching the lanthanum portion for other similar metals.
This may not seem much of a temperature difference, but it meant that YBCO could be kept in the superconducting state using liquid nitrogen, rather than the much more expensive liquid helium. This has inspired lots more studies over the past 20 years. The ultimate objective, the Holy Grail, is to find a material that would superconduct at room temperature, but no one has got there yet.
There are many possible applications for YBCO; for example MRI scanners could be made to operate more cheaply at a higher temperature using liquid nitrogen coolant. At present, though, there are technical problems preventing these commercial applications. One is that in order to superconduct at 95K, the YBCO has to be slightly oxygen-deficient, to have just a bit less than the seven oxygen atoms per yttrium atom. The exact amount is crucial, and tricky to achieve.
Other problems include making the YBCO in the right state; a lot of research is going into making thin films of it and finding a way of making it into a continuous wire, rather than just an assembly of crystals packed together that are unable to conduct decent currents.
Investigators are looking into depositing YBCO on top of flexible metal wires, and research into this continues. Apart from this, there are lots of everyday applications for yttrium compounds In its compounds yttrium is always present as the yttrium three plus ion, which means that it is colourless and has no unpaired electrons; therefore it does not have any interesting magnetic or spectroscopic properties of its own.
The up side of this is that yttrium compounds make very good host materials for other lanthanides. The most familiar application lies in the red phosphor in cathode ray tubes, as used in traditional colour TV sets.
This is made of yttrium oxysulphide, Y2O2S containing a small amount of trivalent europium ions. Similarly, yttrium hosts are often used to accommodate terbium ions, which are green phosphors. Such materials are used in the "cool white" fluorescent lamps. Yttrium aluminium garnet, also known as YAG, is a very important synthetic mineral. It is used to make hard, artificial diamonds, which sparkle just like the real ones.
What is more, by introducing small quantities of lanthanide ions, materials with a range of useful properties can be made. Introduce a small amount of cerium for example, and you have a good yellow phosphor. And erbium gives you an infrared laser. Yttrium also finds use in fuel cells for powering cars and buses, computers and digital phones and, potentially, buildings.
A small amount of yttrium oxide is added to zirconium oxide to make what is known as yttria-stabilized zirconia also called YSZ. That has the unusual property of conducting oxide ions, making it very useful in these fuel cells. YSZ is also used to make the lambda sensors fitted to the exhaust sytem of your car. These monitor the amount of oxygen in the exhaust gases and sends feedback to give the best air-fuel mixture into the engine. So, that is yttrium for you.
Colourless, unspectacular, but undoubtedly fulfilling a lot of important supporting roles. And so the Oscar for best supporting role goes to, you guessed it, Yttrium. Now next week we've got an element that could take us into another dimension. The real element is yet to be discovered - it's a blank space in the Periodic Table just below the halogens. Smith's , however, was a strange material that could be used to open a window to another dimension. He called it a magnetic monopole substance - one that instead of having poles, plural, like an ordinary magnet, had a pole.
Now, whilst no reputable scientist would argue that a magnetic monopole could open an inter-dimensional portal, its existence isn't outside the realms of possibility and if recent reports are anything to go by, it could depend on an otherwise mundane metallic element that you can find skulking around near the bottom of the Periodic Table - holmium. And Hayley Birch will be revealing the truth about such mythical monopoles in next week's Chemistry in its Element.
Until then, I'm Meera Senthilingam and thank you for listening. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. Yttrium never occurs in nature as a free element.
It is found in almost all rare earth minerals and in uranium ores. Yttrium is found in the rare-earth mineral monazite, of which it makes 2. The output of yttrium is about tonnes per year, measured as yttrium oxide, and world reserves are estimated to be around 9 million tonnes. Yttrium is one of the rare chemicals, that can be found in houses in equipment such as colour televisions, fluorescent lamps, energy-saving lamps and glasses.
All rare chemicals have comparable properties. Yttrium can rarely be found in nature, as it occurs in very small amounts. Yttrium is usually found only in two different kinds of ores. The use of yttrium is still growing, due to the fact that it is suited to produce catalysers and to polish glass. Number of Stable Isotopes : 1 View all isotope data. Electron Shell Configuration :. Yttrium Previous Isotopes Next.
Named for the village of Ytterby, Sweden. In , a Swedish chemist named Carl Gustaf Mosander studied yttrium samples and discovered they contained three oxides.
At the time they were called yttria, erbia and terbia. They are now known as white yttrium oxide, yellow terbium oxide, and rose-colored erbium oxide, respectively. A fourth oxide, ytterbium oxide, was identified in Though yttrium was discovered in Scandinavia, it is far more plentiful in other countries.
China, Russia, India, Malaysia and Australia are the leading producers of yttrium. In April , scientists discovered what they think is a massive deposit of rare earth metals , including yttrium, on a small Japanese island called Minamitori Island. Yttrium can be found in most of the rare earth minerals, but has never been discovered in the Earth's crust as a freestanding element.
Lunar rocks gathered during the Apollo moon missions contain yttrium. The human body also contains yttrium in tiny amounts, usually concentrated in the liver, kidneys, and bones. Before the era of flat-screen televisions, TV sets contained large cathode ray tubes, which were large glass tubes that projected images on the screen. Yttrium oxide, doped with the element europium , provided the red color on millions of color-television sets.
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