Originally Posted by
stausty
Also, CO2 liquifies at a much higher temperature than any other easily attainable and safe gas, justifying its use in cartridges.
Actually CO2 is a strange molecule on a few fronts. It goes from a liquid to a solid to a gas through what is called 'sublimation.' And it is the basis of why we breathe. One doesn't so much inhale air (N2 & O2) to get oxygen - that's part of it - but rather we need the O2 to react with C (carbon) in our bodies in order to excrete it. So CO2 is a waste product of humans and other mammals.
When I would buy Nitrogen gas for my chemistry lab at a school I taught at, it was in the form of compressed gas at a very high pressure. Buying it in it's liquid form required a wholly different set-up to contain it. But it had it's uses, too. Such as to prevent very sensitive molecules from decomposing. And using a banana to hammer nails into planks.
As for N2O - which is Nitrous Oxide - laughing gas - I knew a real genius who drove around with a tank of this in his car. One line from the tank went to his souped-up carb. while the other went in his mouth. He knocked out power for blocks when he hit the phone-pole. The police weren't laughing.