OK, I don’t have the quotes I got, but I think I remember that the cost for Xenon was about $700 for a lecture bottle that contains 25 liters (not 2.5 as I incorrectly said above). The lecture bottle itself looks like its volume inside must be somewhat less than a liter, so the pressure inside must be about 25 to 50 atmospheres, and the 25 liters would be the volume its contents would occupy once released to one atmosphere. That means it’s about $700 per cubic foot. It’s got to be 10,000 to 100,000 times as expensive as helium.
I think this is right, but don’t have anything available at the moment to check, and I’m not an experienced xenon user, so I could be wildly off for lack of remembering. I am sure, though, that the price for a small tank was about $700. The next size up, I think, would be a 100 liter bottle. Lecture bottles are the size of a really big heavy flashlight. I think the 100 liter bottles look about like a 1/2 scale or 2/3 scale scuba tank. So I might be confusing these two and it’s $700 for four cubic feet. Still pretty expensive.
OK, you can buy xenon gas from Praxair (203-837-2000). A “lecture bottle” that deliver 25 liters (at atmospheric pressure) costs $717.50. If you are too cheap to spring for this, you can get krypton for $422.89.
You can also buy from Concorde Specialty Gases (Eatontown, NJ 732-544-9899) and get 25 liters for $475. If memory serves, this was a less pure grade than Praxair offered.
Talking with different gases doesn’t change the frequency at which your vocal cords move. It changes the wave speed of sound. Sound waves go 965 m/s in helium, 331 m/s in air, and 120 m/s in sulfur hexafluoride.
It’ll depend how you do it. If you fill an ordinary balloon with the gas and then inhale from the balloon (as is typically done with helium), there shouldn’t be a problem.
having the gas be closer to atmospheric pressure and letting it warm to ambient temperature eliminates two big physical hazards. then you can be concerned with toxicity and oxygen displacement. it takes some to not do hazardously.
Eh? I thought it was specifically the vocal cords going at different speeds in different densities-- um, wait a minute. I see I haven’t thought that through.
Okay, how does the difference in transmission speed equate to a difference in pitch?
Could you explain further?
I understand how the speed changes when the medium changes but for some reason I am imagining a channel of helium travelling out of the persons lung directly to my ear for this to happen.
The sound is produced at the vocal cords and is initially transmitted through helium. At some point the sound enters the new medium of the air. Doen’t its speed change and its pitch lower when it does this?
As was noted upthread, the properties of the gas don’t change the fundamental frequency at which your vocal cords vibrate; that’s determined by the muscular tension on those vocal cords and how much air the person is pushing past them. What does change (with the introduction of a heavier gas) is the resonant properties of your entire vocal tract, which emphasize/deemphasize the harmonic frequencies that determine the timbre of the sound. You can directly alter these resonant properties yourself by changing the shape and position of your tongue and lips; this is how you make all the different vowel sounds, even when singing at a constant pitch. Filling your vocal tract with a heavier gas (one with a lower speed of sound) lowers the resonant frequencies of your vocal tract; you can sing at a concert B-flat with air in your throat and with <a heavier gas> in your throat, and in both cases it’ll be a concert B-flat, but in the latter case it’ll sound as if you were recorded singing at a higher pitch and then played back at a slower speed to bring the pitch back down to a concert B-flat.
Radon decay results in alpha and beta particle emission, a very bad idea to have in one’s lungs. We had a guy at work who’s radon exposure at home was found through bioassays at work, after an 8 hour shift. Intentionally breathing that in would just be crazy.