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  • Hello everyone, today I want to tell you about a rare noble gas: xenon

  • In the periodic table of chemical elements, xenon is located in the last group

  • almost at the bottom.

  • Like its buddy Neon, the heavier Xenon is also part of the noble gas branch.

  • The chemical activity of which is very low, due to the lack of free electrons in the outer electron layer.

  • To provide a simpler example, as a noble gas can be compared the lazy well-fed cat,

  • who doesn't want to take anything, but also has nothing to give.

  • Nevertheless, externally Xenon looks like colourless, odorless gas.

  • To demonstrate the properties of which, i bought a vial of xenon

  • wherein the gas is stored at reduced pressure, so that it is easier to conduct demonstrations with it.

  • Like the other noble gases, while passing a high voltage through xenon,

  • it glows with a beautiful blue color.

  • For the glow, you need to create low pressure in the ampule

  • that is approximately 100 times less than atmospheric and also to pass through the vial

  • at high frequency voltage of about 3000V.

  • This high voltage can be given by the generator of a plasma lamp,

  • from the effect of which a glow discharge occurs in xenon.

  • In other words, the gas starts to glow beautifully.

  • The current here is insignificant. So my hand can easily play the role of a conductor here

  • due to the human body having capacity like in an electrical capacitor.

  • If the vial of xenon is put in liquid nitrogen,

  • The gas inside will freeze,

  • because the melting point of xenon is about -111

  • degrees celsius. When you get the vial out of liquid

  • nitrogen, you can then observe the solid

  • xenon, which quickly melts and immediately

  • evaporates, due to the very small difference

  • between the boiling and melting points of this gas.

  • [music]

  • When chilled with the liquid nitrogen,

  • The vial of xenon lights differently, than when it's at

  • room temperature. It's clearly seen

  • that the gas is ignited already even at the

  • small distance from the wire

  • as the first illumination is close in colour to yellow.

  • After the gradual warm up of the vial,

  • and increase of the pressure, the colour of the plasma

  • becomes more blueish. However

  • this is just us fooling around. In real

  • life, xenon is used in much brighter lamps at which the gas is pressured at about 30 atmospheres.

  • These lamps are just incredibly bright

  • and are mostly used in cinema projectors. In recent times,

  • these lamps are frequently replaced with LEDs,

  • due to the low efficency and complexity of maintenance, besides the first heats up very strongly.

  • Also, in recent years, xenon lamps were put into automobiles increasingly more often,

  • though internally they are made a little bit differently.

  • Xenon here is used only in order to ignite the arc plasma,

  • after which the lamp heats up and inside of it

  • sodium and scandium salts evaporate,

  • those salts is what supports the further glow in this case.

  • Xenon bulbs are much brighter than incandescent bulbs,

  • which often causes frustration for motorists due to it blinding them at night,

  • being too bright.

  • Additionally, all the digital cameras now use a xenon flash,

  • because of the extremely bright glow of this gas at a high voltage discharge.

  • Unfortunately, xenon does not like to engage in chemical reactions,

  • so I can't show you experiments with it.

  • I can say though that this gas reacts with fluorine

  • and later on from the fluorides of xenon you can obtain its oxide and other compounds.

  • However, of all the noble gases, xenon is the most reactive due to the large atomic radius.

  • Forgot to mention that the abundance of xenon in the earth's atmosphere is about 87 parts per billion,

  • the theory says that this small amount is due to the fact that part of the xenon is stored in quartz rocks coupled with oxygen.

  • Though on Jupiter there's a lot more xenon than here.

  • Being on xenon bulbs, this element is now used for general anesthesia

  • as it blocks the NMDA receptor, responsible for the regulation of synopses

  • that is the transmission of nerve impulses from the brain cell to another.

  • Also, the inhalation of this gas during exercise

  • promotes better muscle grow and more effective training.

  • From that, xenon has been added to the least of doping substances.

  • Another interesting application of xenon is in the space ion engines

  • along with cesium because of the large atomic radius.

  • Xenon can be ionised easily and quickly evaporated,

  • thus maintaining stable operation of the ion engine.

  • Such engines were placed on the space craft ''Deep Space''

  • that was launched to conduct asteroid research,

  • as well as the ''Smart 1'' satellite.

  • In the end, we can say that xenon is fairly rare, but also a very useful gas.

  • Now you have learned a little bit of the other elements.

  • If you would like to support the continous production

  • of science videos like this one, please support the channel on Patreon

  • Link in the video description.

  • Please like and subscribe to my channel to see many more of new and interesting.

Hello everyone, today I want to tell you about a rare noble gas: xenon

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キセノン - 地球上で最も明るいガス! (Xenon - THE BRIGHTEST Gas on Earth!)

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    李冠緯 に公開 2021 年 01 月 14 日
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