* KS4 Science GCSE Chemistry Revision Notes GROUP 0 NOBLE GASES helium, neon, argon, krypton, xenon
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Revision KS4 Science IGCSE/O level/GCSE Chemistry Information Study Notes for revising for AQA GCSE Science, Edexcel 360Science/IGCSE Chemistry & OCR 21stC Science, OCR Gateway Science (revise courses equal to US grades 9-10) |
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Keywords * argon uses * compounds * data on elements * electron arrangement * helium uses * introduction * krypton uses * neon uses * radon dangers * xenon uses * uses of noble gases * extra information GCSE m/c QUIZ on Noble Gases (xhtml version) EMAIL query?comment * Multi-word fill worksheet GCE AS/A2/IB Advanced A Level Chemistry Notes on Noble Gases Note: Using 0 to denote the Group number of Noble Gases is very historic now since compounds of xenon known exhibiting a valency of 8. Because of the horizontal series of elements e.g. like the Sc to Zn block (10 elements), Groups 3 to 7 can also be numbered as Groups 13 to 17, and Group 0 numbered Group 18, to fit in with the actual number of vertical columns of elements. This can make things confusing, but there it is, classification is still in progress!
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| Introduction to the Group 0/8 Noble Gases | (see data table below) |
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| The first 3 Noble Gases, showing their electron arrangements with full very stable outer shells. | ![]() |
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| Selected data on the Group 0/8 Noble Gases (more AS-A2 data) | |||||
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Chemical symbol and name |
Atomic number | Electron arrangement | Melting point | Boiling point | Atomic radius pm (10-12m) |
| He helium | 2 | 2 | -272oC , 1K | -269oC , 4K | 49 |
| Ne neon | 10 | 2.8 | -249oC , 24K | -246oC , 27K | 51 |
| Ar argon | 18 | 2.8.8 | -189oC , 84K | -186oC , 87K | 94 |
| Kr krypton | 36 | 2.8.18.8 | -157oC , 116K | -152oC , 121K | 109 |
| Xe xenon | 54 | 2.8.18.18.8 | -112oC , 161K | -108oC , 165K | 130 |
| Rn radon | 86 | 2.8.18.32.18.8 | -71oC , 202K | -62oC , 211K | 136 |
| Uses of the Group 0/8 Noble Gases | ||
| He helium |
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The gas is much less dense than air (lighter) and is used in balloons and 'airships'. Because of its inertness it doesn't burn in air UNLIKE hydrogen which used to be used in large balloons with 'flammable' consequences e.g. like the R101 airship disaster! Helium is also used in gas mixtures for deep-sea divers. |
| Ne neon |
just
like this website!
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Neon gives out light when high voltage electricity is passed through it, so its used in glowing 'neon' advertising signs and fluorescent lights. |
| Ar argon |
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Argon, like all the Noble Gases is chemically inert. It used in filament bulbs because the metal filament will not burn in Argon and it reduces evaporation of the metal filament. It is also used to produce an inert atmosphere in high temperature metallurgical processes, eg in welding where it reduces brittle oxide formation reducing the weld quality. Its bubbles are used to stir mixtures in steel production. Argon is the cheapest to produce. |
| Kr krypton | Not used by superman! BUT is used in fluorescent bulbs, flash bulbs and laser beams. | |
| Xe xenon | Good for winning scrabble games! AND also used in fluorescent bulbs, flash bulbs and lasers. | |
| Rn radon |
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This has almost no uses, but does have dangers! Radio-isotopes of radon are produced by radioactive decay of heavy metals (e.g. uranium) in the ground. Can build up in cellars. Like all radio-isotopes it can cause cell damage (DNA) and ultimately cancer (see link below). However it is used in some forms of cancer treatment |
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Extra 'bits and bobs' on THE NOBLE GASES |
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| % in Air by volume | 0.0005% He, 0.0018% Ne, 0.93% Ar, 0.0001% Kr, 0.00001% Xe, ?% Rn - impossible to be zero, but an extremely minute trace hopefully! (varies with local geology) |
| Radon dangers | Rocks, e.g. granite, can contain uranium metal compounds which are radioactive. When they 'decay' radioactively, radioactive and harmful radon gas can be formed. |
| Compounds of Noble Gases - yes they do exist! |
From the early
1960's compounds have been made, but only xenon compounds are stable and
usually combined with oxygen and fluorine, which, not surprisingly, are
the more reactive non-metals e.g.
Xe + 2F2 => XeF4 (using Ni catalyst 60oC, easy if you know how! and another catalytic bonus from a transition metal!) |
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