So, if you inhale helium, just how long does that James Blunt squeakiness last til you have to hit the balloon again?
I’d like to test it myself, but unfortunately I’ve no balloons at hand.
not more than a minute, usually less, depending on how much helium you intake and how many breaths/how deep your breaths are you take afterwards.
Basically it replaced the air in your vocal chords with much smaller atoms/molecules that resonate at a higher frequency, so basically until those molecules (helium is generally two He atoms, if I remember correctly) are replaced by regular oxygen/nitrogen/everything else that’s in the normal air we breath.
I think it would be somewhat more accurate to say that the effect is due to the higher speed of sound in helium (which is a consequence of its lower density).
The inverse effect is noted with sulfur hexafluoride, as seen in this YouTube clip.
hmmm, maybe. I suck at physics 
That’s the sort of thing I ask my brother. I’m the history guy, hehe
Helium doesn’t combine with anything, including other helium. A helium molecule is a single atom.
Supplemental question: I’ve never done the helium thing, and can think of no reason why I would. But is it dangerous?
If it lasts more than five minutes . . . you’re stuck that way forever.:smack:
OK, more serious answer . . .
Potentially, yeah. If you fill your lungs with helium, then they’re not full of oxygen. Inhale too much at once and you can asphyxiate. There are some documented cases of people dying from helium inhalation (easily found on Google), although it’s certainly only a small fraction of the many people who’ve tried it. I’m guessing the risk is greater for kids than adults, given their smaller lung capacity.
Yes, since it replaces the oxygen in your lungs.
A friend of mine secretly took a breath of helium and started walking into the next room where some friends were, intending to surprise them with his funny voice. Before he got there, he passed out and fell down. He was okay, but obviously, he could have been seriously hurt.