inert gas

[[email protected]]

What kind of inert gas is typically in a lightbulb?

What happens if you let it out and operate the lightbulb without it?

 

[JeffM]

What kind of inert gas is typically in a lightbulb?

bob @coolgroups.com

Read all about it:
http://66.102.9.104/search?q=cache:...ight_bulb+wikipedia+light-bulbs+argon+krypton

What happens if you let it out and operate the lightbulb without it?

Rapid oxidation.

 

[Phil Allison]

What kind of inert gas is typically in a lightbulb?

** Nitrogen - at about 0.5 normal atmospheric pressure.

What happens if you let it out and operate the lightbulb without it?

** A plain vacuum bulb has a very short life as the glass envelope soon
blackens up.

I once tested few 12 volt bulbs where the Asian maker had failed to put in
any - only took a few hours to go all back.

I checked out an unused sample by submerging it in a glass of water and
then crushing the envelope with a pair of pliers.

Result - not one bubble emerged.

Try that with a small bulb yourself.





........ Phil

 

[[email protected]]

** Nitrogen - at about 0.5 normal atmospheric pressure.




** A plain vacuum bulb has a very short life as the glass envelope soon
blackens up.

I once tested few 12 volt bulbs where the Asian maker had failed to put in
any - only took a few hours to go all back.

I checked out an unused sample by submerging it in a glass of water and
then crushing the envelope with a pair of pliers.

Result - not one bubble emerged.

Try that with a small bulb yourself.





....... Phil

you can ad a small amount of gas to a vacuum and it will still be in a
vacuum.... Ive done it with home made plasma globes.....and I do it
nearly every day with hvac systems.... Pull an hvac system down into a
vacuum and you you would be surprised at the volume of gas neccesary to
"break" the vacuum.

 

[Phil Allison]

<cornytheclown

you can ad a small amount of gas to a vacuum and it will still be in a
vacuum....

** Nope.

Ive done it with home made plasma globes.....and I do it
nearly every day with hvac systems...

** Neither of which is anything like a vacuum.

Pull an hvac system down into a
vacuum and you you would be surprised at the volume of gas neccesary to
"break" the vacuum.

** The inside of a CRT is a vacuum.

Same goes for electron tubes.

Same for outer space.


And so s this CLOWN'S brain.




......... Phil

 

[David Harmon]

On 25 Jul 2006 21:00:44 -0700 in sci.electronics.basics,
[email protected] wrote,

What kind of inert gas is typically in a lightbulb?

Nitrogen, argon, xenon, perhaps others
http://en.wikipedia.org/wiki/Incandescent_light_bulb

What happens if you let it out and operate the lightbulb without it?

It soon becomes a darkbulb. Actually, it's letting in oxygen that's
the problem.

 

[jasen]

What kind of inert gas is typically in a lightbulb?

argon is cheapest, sometimes krypton is used as being denser it cools the
filament better at the same pressure.

What happens if you let it out and operate the lightbulb without it?

assuming you let air in the filament turns to white ash wery rapidly
(try it with a small low-voltage lamp)

If you "replace" it with a vacuum that doesn't happen, but the filament
overheats, and evaporates, and ends up as a coating on the inside of the
glass.

quartz-halogen lamps have a reactive gas (flourine or chlorine I think)

Bye.
Jasen

 

[Phil Allison]

"David Harmon"

It soon becomes a darkbulb. Actually, it's letting in oxygen that's
the problem.

** Nope - just the mere absence of the inert gas.

See my earlier post for proof.

Try breaking the glass of a torch bulb and see how the filament lasts only a
few seconds.







......... Phil

 

[Eeyore]

you can ad a small amount of gas to a vacuum and it will still be in a
vacuum....

Er.... NO !

A vacuum means an absence of any gas !

I can see why you have clown in your nick.

Graham

 

[Bob Myers]

Er.... NO !

Right. It will, at the very least, burst into flame if
not outright explode. At least, that's what happened
to Mom's Electrolux when I tried to suck up a spilled
quart or so of high-octane....

So that gas WASN'T in a vacuum for very long, believe
me!

Bob M.

 

[[email protected]]

<cornytheclown


** Nope.




** Neither of which is anything like a vacuum.




** The inside of a CRT is a vacuum.

Same goes for electron tubes.

Same for outer space.


And so s this CLOWN'S brain.




........ Phil

thanks for the correction you motherfucking prick...... I guess you
unemployed guys hanging out in sci basics just sit all day waiting to
insult someone dont you..... asshole....

 

[John Fields]

What kind of inert gas is typically in a lightbulb?

---
That depends on what you mean by "let it out". If you break the
seal and let air in, the atmospheric oxygen will attack the filament
when it gets hot and burn it out in a few seconds or less.

If you mean sucking out all of the nitrogen, then the tungsten will
rapidly evaporate from the filament when it gets hot and condense on
the inside of the envelope, keeping a lot of the photons from
getting loose and, eventually, causing the filament to rupture.

 

[John Fields]

you can ad a small amount of gas to a vacuum and it will still be in a
vacuum....

---
Yes, the gas will be _in_ a vacuum, but its presence will have
destroyed the vacuum since a real vacuum is bereft of matter.
---

Ive done it with home made plasma globes.....and I do it
nearly every day with hvac systems.... Pull an hvac system down into a
vacuum and you you would be surprised at the volume of gas neccesary to
"break" the vacuum.

---
Actually, all it takes to "break" the holy vacuum is one particle of
mass wandering around in there upsetting things.

When you talk about evacuating an HVAC system you're not talking
about a real vacuum, you're talking about sucking out enough air so
that you can replace it with refrigerant and have the charge last
for a number of years before what you left behind or what outgasses
from the installation poisons the system.

 

[John Fields]

^^^^
matter

 

[Dr. Polemic]

** Nitrogen - at about 0.5 normal atmospheric pressure.




** A plain vacuum bulb has a very short life as the glass envelope soon
blackens up.

I once tested few 12 volt bulbs where the Asian maker had failed to put in
any - only took a few hours to go all back.

I checked out an unused sample by submerging it in a glass of water and
then crushing the envelope with a pair of pliers.

Result - not one bubble emerged.

Try that with a small bulb yourself.

What about normal sized household light bulbs. They usually have rated
lives of 750 hours to 1000 hours or so, for all wattage ratings. Since you
said that a plain vacuum bulb has a very short life, that would imply that
household bulbs (of all wattage ratings) are always gas filled. Is that
so?

 

[Phil Allison]

"Dr. Polemic"

What about normal sized household light bulbs. They usually have rated
lives of 750 hours to 1000 hours or so, for all wattage ratings. Since
you
said that a plain vacuum bulb has a very short life, that would imply that
household bulbs (of all wattage ratings) are always gas filled. Is that
so?

** Vacuum tungsten filament lamps were once the norm - over 60 years ago.

They have much less light output for the same wattage and do go black.

Possibly some of the low power and low brighness " pilot lamps " used in
fridges / ovens etc are vacuum types.

Bust one underwater and see.





........ Phil

 

[Rich Grise]

I doubt if there's anything even approaching a "perfect" vacuum anywhere
in the known Universe. ALL vacuums are "partial vacuums", the only
difference is how close to 0 molecules you can get.

I used to work for a place where they made a big vacuum bell jar with
all kinds of electron guns and ion guns, and how many different kinds
of vacuum pumps - lessee, they'd start by baking out the system at air,
and then close it all up, let it cool, and they'd use LN2/zeolite sorption
pumps for the first stage, then they'd turn on the ion pumps, and when
they got it clean enough, they'd turn on the titanium getter pump. For
molecular-beam epitaxy, and other processes where they needed an
excriciatingly clean vacuum (remember, 'vacuum' implies 'partial vacuum'),
they used a cryopump, which used a liquid helium chiller to condense
out everything that's left in the chamber.

Very interesting stuff!

Cheers!
Rich

 

[Rich Grise]

^^^^
matter

All matter has mass - does all mass have matter? ;-)

Cheers!
Rich

 

[Guest]

Might I suggest that the question of "what situation can I call a vacuum and
not have people jump all over me" is a political matter? Maybe we can leave
the word "vacuum" to the people "vacuuming" carpets, and just specify parts
per cubic kilometer when we want to be specific and scientific.

 

[John Fields]

I doubt if there's anything even approaching a "perfect" vacuum anywhere
in the known Universe.

---
Sure there is. A given volume of space will enclose a perfect
vacuum as long as no matter enters that volume.
---

ALL vacuums are "partial vacuums", the only difference is how close to
0 molecules you can get.

---
Zero _particles_, actually. And no, some vacuums are perfect some
of the time. For example, take a cubic meter of space out there
somewhere where a lone hydrogen atom goes zipping through that
volume every hour or so. During the time the atom is in there the
vacuum won't be perfect, but during the times isn't in there it
_will_ be a perfect vacuum.