Ya helium is lighter then air that makes u sound like a chipmunk there was another gas that i don't remember the name of that makes your sound very deep because it is heavier than air.
The answer is that the higher speed of sound in helium changes the resonances of your vocal tract. In particular, the formants or resonant frequencies are higher. These formants affect the timbre of your voice, as well as what vowel people hear. It's the change in timbre that people notice in helium voice. This sometimes makes them mistakenly think the pitch of the voice is higher.
I think that covers it
If you want more in depth answers/detail, i got this from Here.
If you suck helium straight from the pressured can, there is a high chance of fatality because there is not enough oxygen to counteract all the helium and keep to alive.
You should only take some from a balloon and in a tiny amount, like a slit second. But even then, don't do it unless it is necessary for an experiment or something...
Well actually it is only fatal when taken in large amounts, without any intake of air.
And I'm not sure what the gas is called, but there is something that is much denser then air. it makes your voice sound deep, like....satan or something. I'm not sure you can get it anywere easily, but its still cool.
Ya helium is lighter then air that makes u sound like a chipmunk there was another gas that i don't remember the name of that makes your sound very deep because it is heavier than air.
