What makes tungsten special




















The two-name confusion arises from early mineralogy. The name 'tungsten' is derived from the old Swedish name for 'heavy stone', a name given to a known tungsten-containing mineral.

The name 'wolfram' comes from a different mineral, wolframite, which also has a high content of the element we call tungsten. However in 'wolfram' was dropped and tungsten became the sole official IUPAC name for this element.

However, wolfram did not go down without a fight! In particular the Spanish chemists were unhappy to see the change - not least because their compatriots the Delhuyar brothers are credited with the discovery of the element and its isolation from the mineral wolframite. In their original paper, the Delhuyar brothers requested the name wolfram for the newly isolated element, saying 'We will call this new metal wolfram, taking its name from the matter of which it has been extracted.

Although this may be a compelling case, IUPAC argues that is that its working language is English and so Tungsten is the most appropriate name.

They make the point that students will have to learn some history of chemistry to know why the element symbol is W. The same is true also for a number of other elements, such as potassium, mercury, and silver whose symbols bear no relation to their English name. However, it seems unlikely to me that such a colourful name as wolfram will be forgotten. In case you were wondering, it is believed to be derived from the German for 'wolf's foam'. Many centuries ago mid-European tin smelters observed that when a certain mineral was present in the tin ore, their yield of tin was much reduced.

They called this mineral 'wolfs foam' because, they said, it devoured the tin much like a wolf would devour a sheep! Thus over time the name 'wolframite' evolved for this tungsten-containing ore. In contrast to its semi-mythical role in early metallurgy, these days the applications of tungsten are highly technological, making use of its hardness, stability and high melting point.

Current uses are as electrodes, heating elements and field emitters, and as filaments in light bulbs and cathode ray tubes. Tungsten is commonly used in heavy metal alloys such as high speed steel, from which cutting tools are manufactured. It is also used in the so-called 'superalloys' to form wear-resistant coatings. Its density makes it useful as ballast in aircraft and in Formula one cars and more controversially as supersonic shrapnel and armour piercing ammunition in missiles.

It seems to me that the name tungsten, or 'heavy stone', is justified by these applications, which exploit its strength and density. I'm glad, though, that the birth of chemistry in the activity of those ancient metallurgists and mineralogists is still celebrated by the use of the symbol W for element This ensures that we never forget that there was a time, not so long ago, when many chemical processes could only be explained through metaphor.

I always used to remember tungsten's letter W as standing for the wrong symbol, but can you think of the one letter of the alphabet that isn't used in the periodic table? Now there's something to ponder on. Next week we'll meet the element that was introduced to the world in, its fair to say, a pretty unusual way.

The first hint the world had of the existence of Americium was not in a paper for a distinguished journal but on a children's radio quiz in Seaborg appeared as a guest on MBC's Quiz Kids show where one of the participants asked him if they 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 And Brian Clegg will be telling the story of the radio active element americium and how it keeps homes safe in next week's Chemistry in its element, I hope you can join us. I'm Chris Smith, thank you for listening and 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 Tungsten. View videos about. Help Text.

Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. 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.

Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Juan and Fausto Elhuyar. Origin of the name. The name is derived from the Swedish 'tung sten' meaning heavy stone. Melting point. Boiling point. Atomic number.

Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database. Below are five fun facts about tungsten. You might be surprised to learn that tungsten has the highest melting point of all metals. Like all metals, it will melt when exposed to enough heat. With a melting point of over 3, degrees Fahrenheit, however, it takes more heat to melt tungsten than any other metal on the planet. To put that number into perspective, the melting point of aluminum is just 1, degrees Fahrenheit.

Not only does tungsten have the highest melting point of all metals, but it also has the highest tensile strength. Tungsten has a tensile strength of about 50, to 60, pounds per square inches PSI , which is more than any other material.

Tungsten is frequently used in light bulbs where it serves as the filament for their heating elements. Incandescent light bulbs, for instance, often feature a tungsten-based filament. When activated, the tungsten filament heats up, thereby producing light. Tungsten works well in light bulb filament because of its highly conductive properties. As electricity flows through the tungsten filament, the light bulb illuminates. To find this new filament, Whitney planned a strategy like a military campaign.

Whitney gazed at osmium and its neighbors on the periodic table, using them as clues for where to start his search for filament materials. He gave each of his 30 scientists elements to appraise. Their assignment was simple, but not straightforward: Find a metal that could form a hairlike filament and withstand heat up to thousands of degrees Celsius as electricity passed through it, like the coils within a toaster.

Ideally, the material should remain inert to the small amounts of oxygen within bulbs, to avoid a common reaction that dimmed light. Additionally, Whitney instructed his scientists to explore a family of elements known as refractory metals , which were notorious for being extremely difficult to machine because of their resistance to wear.

Other scientists had experimented with tungsten bulbs before William D. Coolidge, but he was the first to manufacture ductile filaments that were flexible enough to bend without breaking. General Electric manufactured this Mazda B bulb patent drawing, inset in Coolidge was assigned to work on tantalum, located in one column of the periodic table.

He also investigated two metals from the adjacent column, molybdenum and tungsten, that were twice and thrice as hard. For months, Coolidge focused on tantalum, a metal that researchers in Germany had fashioned into filaments. When supplied with direct current, tantalum light bulbs burned for more than hours—more than a month. But their lifespan plummeted by 70 percent with alternating current, which was predominant on American electrical grids. Sections of the tantalum threads became brittle from the electricity and broke when pulsed by the alternating jolts.

Coolidge made little progress with tantalum and worked briefly with molybdenum before he eventually focused on tungsten.

With the highest melting point of all the elements of the periodic table 3, degrees , tungsten glows white-hot without melting as electricity passes through it.

It renders lifelike colors rather than the yellowish hue of earlier bulbs. Scientists usually worked with metals by heating and softening them, but most tools could not sustain the temperatures needed to mold tungsten. Tungsten is also an unforgiving, hard, and brittle metal. The project almost seemed hopeless, Coolidge noted at the time, but the team persevered. Coolidge used the next best starting point for tungsten—its powder form.

Using a hydraulic press, he squeezed it into a bricklike shape and fused together the powder with electricity by sintering it with a mercury-arc furnace.

Then Coolidge attempted to extrude this tungsten chunk, which he called a rod, through a hole to form a filament, but the metal would not comply. After months of trying to muscle tungsten into a filament, he attempted another approach. Coolidge poured tungsten powder into a binder made from starch and other organic compounds, mixed it together, and then squirted out a filament.

When he tested the bulb, the inside of the glass blackened from the scorched binder. He used trial and error to develop a process for taming tungsten into ductile, durable light bulb filaments that could be manufactured in massive quantities. He started with tungsten powder right, top , which was pressed into bricklike chunks called rods right, center. To produce the filaments right, bottom for incandescent light bulbs, he modified a process called swaging, which drew the metal through diamond dies of ever smaller diameters.

In March , a breakthrough happened when a spongy rod of tungsten accidentally fell into a pool of liquid mercury from the sintering furnace, and the mercury filled the pores. Coolidge then recalled getting a tooth filled as a child. His dentist had prepared the amalgam by combining silver slivers, shaved off of a Mexican coin, into liquid mercury; the young Coolidge noticed that this sticky paste was moldable before it stiffened into a permanent shape.

Coolidge realized that mercury could be mixed with tungsten and then squirted into wire. The filament glowed stably inside a light bulb. So Coolidge was tasked with making a more robust version that could withstand harsher conditions such as vibrations in cars and trains.



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