Speaker 1: Welcome to brain Stuff from How Stuff Works. Hey everybody,
Speaker 1: it's me Christian Seger, and I am back with another
Speaker 1: brain stuff question. Why can't we breathe underwater? I haven't
Speaker 1: met everybody, but everyone that I have met has not
Speaker 1: been able to breathe underwater, except for aquaman of course.
Speaker 1: And it's a good question when you think about it,
Speaker 1: because water is made up of hydrogen and oxygen, right, well,
Speaker 1: it goes in the chemicals. There's one thing we need
Speaker 1: to remember though, about those chemicals. It's that once they
Speaker 1: react in certain ways, they form compounds that are often
Speaker 1: nothing like their original elements. Think of two solo artists
Speaker 1: from different bands and then they get together and they
Speaker 1: make an album that sounds nothing like the original music.
Speaker 1: For example, if you react carbon, hydrogen, and oxygen together
Speaker 1: one way, you get glue close, But if you react
Speaker 1: them together another way, you get vinegar. And if you
Speaker 1: react them yet another way, you get fat. And if
Speaker 1: you react them yet another way, you get ethanol and gluclose. Fat,
Speaker 1: ethanol and vinegar are nothing like each other, but they're
Speaker 1: all made from the same elements. In the case of
Speaker 1: hydrogen and oxygen gas, if you react them together one
Speaker 1: way you get liquid water, and the reason we can't
Speaker 1: breathe liquid water is because the oxygen used to make
Speaker 1: the water is bound to two hydrogen atoms, and we
Speaker 1: can't breathe that resulting liquid. The oxygen that fish breathe
Speaker 1: is not the oxygen that's in H two O. Instead,
Speaker 1: the fish are breathing O two oxygen gas, and that's
Speaker 1: dissolved in that water. Many different gases dissolve in liquids,
Speaker 1: and we can see an example of this all the
Speaker 1: time with carbonated beverages. In knees beverages, there's so much
Speaker 1: carbon dioxide gas dissolved in the water that it rushes
Speaker 1: out in the form of bubbles. Fish breathe that dissolved
Speaker 1: oxygen out of the water using their gills, and it
Speaker 1: turns out that extracting the oxygen isn't that easy. Air
Speaker 1: has something like twenty times more oxygen in it than
Speaker 1: the same volume of water. Plus let's remember that water
Speaker 1: is a lot heavier and thicker than air, so it
Speaker 1: takes a lot more work to move it around. The
Speaker 1: main reason that gills work for fish is the fact
Speaker 1: that fish are cold blooded. This reduces their oxygen demands
Speaker 1: tremendously warm blooded animals like whales breathe air like people
Speaker 1: do because it would be hard to extract oxygen using gills.
Speaker 1: Human beings can't breathe underwater because our lungs don't have
Speaker 1: enough surface area to absorb enough oxygen from water, and
Speaker 1: the lining of our lungs is adapted to handle air
Speaker 1: instead of water. However, there have been experiments with humans
Speaker 1: breathing other liquids like fluorocarbons. Fluorocarbons can dissolve enough oxygen
Speaker 1: and our lungs can draw that oxygen out. It's just
Speaker 1: that first breath where you suck in the floral carbons
Speaker 1: and they enter your lungs. That is not very pleasant,
Speaker 1: but it is possible. And look, please, nobody out there
Speaker 1: try to breathe underwater, because unless you're an extraordinary person
Speaker 1: or maybe a mutant, you're probably going to drown. Check
Speaker 1: out the brain stuff channel on YouTube, and for more
Speaker 1: on this and thousands of other topics, visit how stuff
Speaker 1: works dot com.