Sulphur Hexafluoride
 

It's a gas, but it's heavy.
Check out the YouTube video.

Denser. It's denser than air. Grrr, pet peeve.

It's also a very potent greenhouse gas.

But it is still close to right to say it is heavier. The molar mass of air is 29g/mol. The molar mass of sulphur hexaflouride is 146 g/mol. So it is 6.13 times denser than air and 5.03 times heavier.

While it is heavier, that's not what people tend to mean when they say "heavier". Just because in this case the distinction is lost in terms of observable effect, doesn't mean they don't have distinct meanings.

I know the distinction, just pointing out that even though they weren't saying what they meant, what they said was still almost technically correct.

As am I sometimes.

Fun video. I wonder if it cause any headaches like helium can?

Yes, most likely. That would be due to the lack of oxygen getting to the brain. It also can cause asphyxiation followed closely by death.

But ... is it fun on Space Mountain?




That's the question. :iSm:

I don't know if it is in the video (it won't play for me) but if breathed it will make your voice lower, the opposite of helium. That's how Isaac Hayes does it.