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Author Topic: will tungsten filament react with inert gas ?  (Read 789 times)

Offline Hari Krishna

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will tungsten filament react with inert gas ?
« on: 19/03/2016 17:49:21 »
will the tungsten react with inert gas in light bulb (incandescent)  in the presence of ionising radiation ?


 

Offline Bored chemist

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Re: will tungsten filament react with inert gas ?
« Reply #1 on: 19/03/2016 17:56:41 »
Yes and no. It will donate an electron back to the ionised gas.
No actual compound will be produced.
 

Offline evan_au

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Re: will tungsten filament react with inert gas ?
« Reply #2 on: 19/03/2016 22:14:49 »
Even without ionizing radiation, or reaction with the inert gas, hotspots in the tungsten filament will cause the tungsten to evaporate (making the hotspot higher resistance and even hotter, causing more evaporation...) until the filament fails.

This causes visible darkening of the glass.

See: http://en.wikipedia.org/wiki/Incandescent_light_bulb#Reducing_filament_evaporation
 

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Re: will tungsten filament react with inert gas ?
« Reply #2 on: 19/03/2016 22:14:49 »

 

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