Once past the epidermis, HF starts to dissociate, unleashing the highly-reactive fluoride ion. Free fluoride binds tightly to both calcium and magnesium, forming insoluble salts which precipitate into the surrounding tissues. Robbed of their co-factors, critical metabolic enzymes can no longer function, cells begin to die, tissues to liquefy and bone to corrode away.
And if calcium loss is rapid enough, muscles such as the heart stop working. Burns with concentrated HF involving as little as 2. These brave scientists were battling to be the first to isolate elemental fluorine F 2 from its various compounds, using electrolysis.
To achieve this feat, Moissan not only had to contend with HF - the preferred electrolyte in such experiments - but fluorine itself, a violently reactive gas.
Moissan's feat earned him the Nobel Prize in chemistry, but the celebration was short-lived. Another victim of fluorine's toxic effects, he died only two months later. Yet Moissan's method lived on, and is used today to produce multi-ton quantities of fluorine from its ore fluorspar. The top-selling anti-depressant Prozac, the cholesterol-lowering drug Lipitor, and the antibacterial Cipro, all have fluorine to thank for their success.
How is this possible? Because the flip side of fluorine's extreme reactivity is the strength of the bonds it forms with other atoms, notably including carbon. This property makes organofluorine compounds some of the most stable and inert substances known to man. Fluorine's special status also stems from the 'fluorine factor', the ability of this little atom to fine-tune the chemical properties of an entire molecule.
For example, replacing hydrogen with fluorine can protect drugs from degradation by metabolic enzymes, extending their active lifetimes inside the body. Or the introduced fluorine can alter a molecule's shape so that it binds better to its target protein. Such precise chemical tinkering can now be carried out in pharmaceutical labs using an array of safe, commercially-available fluorinating agents, or the tricky transformations can simply be out-sourced to someone else.
Most of us also have fluorine to thank for our beaming smiles. The cavity-fighting agents in toothpaste are inorganic fluorides such as sodium fluoride and sodium monofluorophosphate. Fluoride not only decreases the amount of enamel-dissolving acid produced by plaque bacteria, but aids in the tooth rebuilding process, insinuating itself into the enamel to form an even harder surface which resists future attack.
And the list of medical applications doesn't stop there. Being put to sleep is a little bit less worrisome thanks to fluorinated anaesthetics such as isoflurane and desflurane, which replaced flammable and explosive alternatives such as diethyl ether and chloroform. Fluorocarbons are also one of the leading candidates in development as artificial blood, as oxygen is more soluble in these materials than most other solvents.
And radioactive fluorine 18 F rather than the naturally-occurring 19 F is a key ingredient in positron emission tomography or PET , a whole-body imaging technique that allows cancerous tumours to be discovered before they spread. Fluorochemicals are also a mainstay of industry. One of the most famous is the polymer polytetrafluoroethylene, better known as Teflon, which holds the title of world's most slippery solid. Highly thermostable and water proof, it's used as a coating for pots and pans, in baking sprays, and to repel stains on furniture and carpets.
Heating and stretching transforms Teflon into Gore-tex, the porous membrane of sportswear fame. Gore-tex's pores are small enough to keep water droplets out, while allowing water vapour that is, sweat to escape. So you can run on a rainy day, and still stay dry.
Fluorine plays another important role in keeping you cool, as air-conditioning and household refrigeration units run on energy-efficient fluorocarbon fluids. And fluorine's uses are not limited to earth.
When astronauts jet off into space they put their trust in fluoroelastomers, a type of fluorinated rubber. Fashioned into O-rings and other sealing devices, these materials ensure that aircraft remain leak-free even under extreme conditions of heat and cold.
And when accidents do happen, space travellers can rely on fluorocarbon-based fire extinguishers to put the flames out. Fluorine has long been known as the 'tiger of chemistry'.
And while the element certainly retains its wild side, we can reasonably claim to have tamed it. As only a handful of naturally-occurring organofluorine compounds have ever been discovered, some might argue that we now make better use of fluorine than even Nature herself. So Teflon is acknowledged as the world's most slippery thing and I bet there are one or two politicians knocking around who are thanking fluorine for that.
Next week. I cannot imagine that this is all someone would be saying if they were unfortunate enough to be stricken with the disease of the same name. The ouch-ouch disease. The disease results from excessive cadmium poisoning and was first reported in a small town about miles north west of Tokyo. Rice grown in cadmium contaminated soils had more than 10 times the cadmium content than normal rice. The ouch-ouch-ness of this disease resulted from weak and brittle bones subject to collapse due to high porosity.
And you can find out about the ouch-ouch factor with Steve Mylon when he uncovers the story of cadmium on next week's Chemistry in Its Element. 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 Fluorine. View videos about.
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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 Up to 50 ppb has been recorded in city environments. Small amounts of fluorine are naturally present in water, air, plants and animals. As a result humans are exposed to fluorine through food and drinking water and by breathing air. Fluorine can be found in any kind of food in relatively small quantities.
Large quantities of fluorine can be found in tea and shellfish. Fluorine is essential for the maintenance of solidity of our bones. Fluorine can also protect us from dental decay, if it is applied through toothpaste twice a day.
If fluorine is absorbed too frequently, it can cause teeth decay, osteoporosis and harm to kidneys, bones, nerves and muscles. Fluorine gas is released in the industries. This gas is very dangerous, as it can cause death at very high concentrations. At low concentrations it causes eye and nose irritations. When fluorine from the air ends up in water it will settle into the sediment. When it ends up in soils, fluorine will become strongly attached to soil particles.
In the environment fluorine cannot be destroyed; it can only change form. Hydrofluoric acid, as another example, can also prove to be fatal when even a small splash on the skin occurs, according to Chemicool. In the environment, fluorine, the 13th most abundant element in Earth's crust, typically settles within the soil and readily combines with soil, rock, coal and clay, according to Lenntech. Plants may absorb the fluorine from the soil, although high concentrations can lead to damage.
Corn and apricots, for example, are among the plants that are most susceptible to damage and growth reduction when exposed to elevated levels of fluorine. Although fluorine can be toxic when the concentration within the body is too high, it can also be a beneficial element to include in cancer drugs, according to a article published in the Journal of Fluorine Chemistry.
According to the research, replacing carbon-hydrogen or carbon-oxygen bonds with a carbon-fluorine bond in the active components of the drug usually shows an improvement of the drugs' effectiveness, including higher metabolic stability, increased binding to target molecules, and enhanced membrane permeability. It is hoped that with the increased effectiveness of the drugs, in conjunction with tumor-specific target drugs or targeted drug delivery systems, the quality of life of cancer patients can be greatly improved over traditional methods such as chemotherapy, in which cancer cells, as well as healthy cells, are targeted by the drugs.
This new generation of cancer-fighting drugs, as well as fluorine-probes to deliver the drugs, has been tested against cancer stem cells and has shown promise in targeting and fighting the cancer stem cells, according to the study. The researchers found that the drugs that included fluorine were several times more active against various cancer stem cells and exhibited better stability than traditional cancer-fighting drugs.
This article was updated on Nov. Live Science. Rachel Ross. He did this through the electrolysis of potassium fluoride KF and hydrofluoric acid HF. He also completely isolated the fluorine gas from the hydrogen gas and he built his electrolysis device completely from platinum. His work was so impressive that he was awarded the Nobel Prize for chemistry in Today, fluorine is still produced through the electrolysis of potassium fluoride and hydrofluoric acid as well as through the electrolysis of molten potassium acid fluoride KHF 2.
Fluorine is added to city water supplies in the proportion of about one part per million to help prevent tooth decay. Hydrofluoric acid HF is used to etch glass, including most of the glass used in light bulbs. Uranium hexafluoride UF 6 is used to separate isotopes of uranium.
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