Noble gases have very low reactivity. This makes them useful for applications where chemical reactions are unwanted. Xenon is found and obtained from the atmosphere. When voltage is applied across an electrode in xenon gas it produces a bright flash light, so it has long been used in light bulbs used for flash photography and lasers.
There is no known biological role for xenon but it does have specific beneficial effects on the body that are used in medicine.
Xenon is in group 18 and period 5. Group 18 elements are known as noble gases, and include helium, neon , argon, krypton , xenon, radon, and a theoretical element called oganessen.
Noble gases are inert, which means that they do not readily react with other elements. It can be made to react under very extreme laboratory conditions and with elements that have high electronegativity. It was first discovered as a small fraction of air and named xenon, after a Greek word that means foreigner, stranger, or guest. Xenon is a colorless, odorless, dense gas.
As a noble gas, it has very low reactivity and electronegativity. Therefore, it is inert and usually maintains an oxidation state of 0. Consistent with the trend that atomic radius increases down groups, xenon is the largest known noble gas. When voltage is applied to an electrode in xenon gas, it produces a characteristic blue light. It is non-toxic but can have effects on the body when it is inhaled.
Xenon is a gas at room temperature. It has a low melting point of Nowhere on Earth has ever been measured to be this cold. It is less dense than the other noble gases as well as hydrogen , oxygen, nitrogen, fluorine , and chlorine gases. Xenon has 8 valence electrons. This is the hallmark of the noble gases and the reason that they are inert. Having a full valence shell is the most stable electron configuration that an atom can have.
That is why most chemical compounds are stable when they are made up of atoms that have achieved noble gas configuration by donating, receiving, or sharing electrons. Therefore, an oxidation state of 0 is most common for xenon.
However, under extreme conditions, xenon is able to form compounds easier than any other noble gases. This is because of its size. As the largest noble gas, its valence shell is the furthest from the nucleus.
Therefore, the electrostatic force, or attraction, between the electrons and protons is lower than the other noble gases. Greek: bromos , "stench" elemental bromine is a reddish-brown liquid with a terrible smell. Named after the Greek word for the mineral calamine, cadmia. Calamine is a mineral form of zinc carbonate; cadmium was first observed as an impurity in some calamine ores.
Latin: caesius , "sky blue" salts of cesium produce a blue color when heated. Latin: chloros , "greenish-yellow" elemental chlorine is a pale, yellow-green gas. Greek: chroma , "color" because of the wide variety of colorful salts it produces. German: kobold , "goblin" because of the toxic fumes of arsenic that were produced when silver miners heated the arsenic-containing ore smaltite, mistaking it for silver ore.
Old English: coper , which in turn along with the symbol Cu was derived from the Latin cuprum , "from the island of Cyprus" the leading supplier of copper in the Mediterranean at the time of the Roman empire. Greek: dysprositos , "hard to get at" because the first isolation of the element required a tedious separation sequence. Named for the mineral gadolinite, which was in turned named after Johan Gadolin, the Swedish chemist who first investigated it.
Named after the Latin word for France, Gallia the country in which it was discovered. Anglo-Saxon name for the metal; the symbol Au is from the Latin name, aurum , "shining dawn". Greek: helios , "Sun" helium was discovered in an analysis of the light emitted from the Sun's corona during a solar eclipse.
Latin: indicum , "indigo" after the bright violet line of its atomic spectrum. Anglo-Saxon: iren ; the symbol Fe comes from the Latin name, ferrum. Greek: kryptos , "hidden" since it had been "hidden" in a sample of argon. Ramsay and Travers examined the heavier gas in a vacuum tube and saw that it emitted a beautiful blue glow.
They categorized the new gas as inert and called it xenon, derived from the Greek "xenos," which means stranger. However, in Neil Bartlett proved that xenon was not, in fact, inert. It could cause reactions and compounds. He proved this by making a fluorine derivative. Since then, more than xenon compounds have been made, according to the Royal Society of Chemistry. Natural xenon has nine stable isotopes and 20 unstable isotopes.
Some compounds that can be formed with xenon include difluoride, xenon deuterate, xenon trioxide, sodium perxenate, xenon hydrate, tetrafluoride and hexafluoride. Another interesting compound is a metallic xenon created by using massive amounts of pressure.
Xenon is a trace gas found in the Earth's atmosphere to the extent of about one part in 20 million, According to the Los Alamos National Laboratory. This makes it very rare. It is also found in Mars' atmosphere at 0. This noble gas can also be found down on Earth. Some mineral springs emit xenon. Companies obtain the gas for commercial use from industrial plants that extract the gas from liquid air.
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