Liquid Air

[AndyJ]

The other night I watched a film called ‘The Abyss’. For those who haven’t seen it it’s set deep under the ocean.

In one of the scenes a diver puts a suit on and ‘liquid air’ is pumped into the helmet. At first the diver struggles but then can breath. One of the other actors says something like, “You breathed in your mothers womb and it’s no different”.

So my question is…

Does such a breathing system exist and why would you need it?

[Mangetout]

it’s possible to do things like this using chemicals called oxygenated perfluorcarbons; the downside is that the chemicals tend to be quite harmful.

[therealblaze]

Question: Would it be possible for humans to breathe liquid oxygen?
June Hagberg

Answer: Liquid oxygen is very cold, more than 200 degrees below zero on the
centigrade scale. At this temperature all of the desirable physical
properties of the lung would be nonfunctional. To get an idea of how
the flexibility of the lung would change, place a carnation in some liquid
nitrogen or a super deep freeze. Your question is interesting though
because it would be desirable to breath liquid instead of gas under
certain conditions. Special liquids are being designed to carry dissolved
gaseous oxygen to the lung and to remove carbon dioxide. Even fish are
breathing dissolved oxygen, the water is much too warm for liquid oxygen.
Michael B Lomonaco

From Ask a scientist. Of course oxygen could be liquefied by pressure and not by temperature…

[Mangetout]

Sounds like they might have worked out some of the bugs with liquid breathing of Perfluorocarbons; here is a page where they seem to be offered as a medical product.

Try a Google search for “perfluorocarbons breathing liquid”

[AndyJ]

So it’s possible to breath ‘liquid air’ but what use would that be to a deep sea diver?

[Qadgop_the_Mercotan]

*Originally posted by AndyJ *
**So it’s possible to breath ‘liquid air’ but what use would that be to a deep sea diver? **

Because by using them, divers can go much deeper. When their lungs are full of air, which is highly compressable, and they go too deep, they are crushed (oversimplification, I know).

[AndyJ]

It’s to do with compression. Being a science simpleton I do at least understand that air can be compressed but liquid can’t.

Thanks.

[WIGGUM]

Several other threads have discussed this as well and can be found here: http://boards.straightdope.com/sdmb/showthread.php?threadid=49254

[scr4]

I seem to recall that the demonstration with the mouse in The Abyss was real.

[micco]

Another recent thread with lots of links:
http://boards.straightdope.com/sdmb/showthread.php?threadid=88062

[KneadToKnow]

*Originally posted by AndyJ *
Being a science simpleton I do at least understand that air can be compressed but liquid can’t.

You will, I hope, forgive me, AndyJ, if that was not sarcasm.

I’m a little short-fused right now, though, and Qadgop is one of my best friends around here, so I’m going to have to clear my throat on his behalf and point out that if that was sarcasm, you’ve only shown off what a “science simpleton” you are because it is true that liquids are much less compressable than gases. Solids are even less so.

Again, if it wasn’t sarcasm, please accept my apologies.

[AndyJ]

Nope mate I wasn’t taking the Mic. Or if I was. Only out of myself for not thinking hard enough and coming up with the answer.