If water is made up of hydrogen and oxygen, why can't we breathe underwater?

I am taking chemistry at school, but its one of my worst subjects. I'll try to answer it to my best, though. You can't breath under water because it is in liquid form, which would just fill up your lungs. When water is in gaseous form, steam, however, you can breathe it. As long as something is not poisinous, you can breathe it in gas form. However, I don't know of anything that you can safely breathe while it is in the liquid state of matter.

well water is liqued as we all know. It will flood your lungs to the point we can not breath we breaths oxyogen because it is solly gas not any other for with any other type of form.

Hydrogen and oxygen gas, if you react them together one way you get liquid water (H2O). The reason we cannot breathe liquid water is because the oxygen used to make the water is bound to two hydrogen atoms, and we cannot breathe the resulting liquid. The oxygen is useless to our lungs in this form. The oxygen that fish breathe is not the oxygen in H2O. Instead, the fish are breathing O2 (oxygen gas) that is dissolved in the water. Many different gases dissolve in liquids, and we see an example all the time in carbonated beverages. In these beverages, there is so much carbon dioxide gas dissolved in water that it rushes out in the form of bubbles.

well you are correct my friend that water is made of hydrogen and oxyegen,... but its in a pure form of hydrogen and oxygen... we as human need more than just oxygen to breath ,... ie., we need oxygen, hydrogen vast amount of nitrogen, little amount of carbon dioxide and we would need this in gaseous state that would be our requirement,... but water is not in gaseous state.,.. if there was some way of actually making separation of these molecules and also the other ingredients are added in proper proportion then we would be able to breath underwater...

Well you are definitely not talking about decomposing water to get Hydrogen and oxygen and then breathing that Oxygen I believe? :) Actually water does contain quite a large amount of disolved gases, this enables fishes to breathe underwater, they have gills, which are designed to absorb disloved air from the water as it passes over the gills, but we dont have gills :( And this doesnot enable us to breathe underwater.

My friend, we need elemental oxygen to carry out the life processes. We need to breathe as we need oxygen to carry out respiration i.e internal oxidation of food to release energy which is vital for life. We cannot breathe in water because our lungs cannot break water into hydrogen and oxygen. Moreover, our lungs are made to absorb gases by diffusion and not liquids.

It is because humans don't have gills but lungs! Our lungs aren't created to breathe underwater or else we will drown. In the movie ABYSS, the "divers" wore a "helmet with water in it" (lol, sorry i don't know the term!).The thing was a protection, for sudden change of water pressure or temperature, i can't remember.. I'm just curious, how was it possible? How can they breathe in water? I guess i missed that part.. :)

I think it's because our lungs can't separate the oxygen from the hydrogen in the water. I remember some studies done in the nineties showing that mammals can breath liquid oxygen. I saw the report on CNN at the time, and it showed this mouse submerged in liquid oxygen. The mouse fought like it was drowning, until it finally gave up, and started breathing normally in the liquid oxygen.

water is a compound.that means two hydrogen atoms and one oxygen atom has chemically reacted to produce H2O. The H2O molecules are held together by hydrogen bonds. this makes it very difficult to break as hydrogen bonds are one of the strongest bonds.this is why it is liquid at room temperature. humans have two pipes that are interconnected. the windpipe and the other is the one that leads to your abdomen. they are separated only by a cartilage. when u take in water, it will be recognized as liquid and will go into your stomach.therefore when we try to 'breathe' underwater, the body will just take in the fluid surounding it.even if u force water through your windpipe there is no mechanism that our body has that is able to break the forces holding the strong hydrogen bonds in the water. these bonds can only be brokin by passing an electrical current of high voltage through a beaker of water. since or lungs don have that, we cant possibly breather underwater of course unless we have gills like the fishes and some amphibians which works via a different process in trapping oxygen.

In water hydrogen and oxygen are bonded together. The oxygen we breathe is pure oxygen gas which isn't bonded to anything else. There are a lot of other compounds which contain oxygen but you cannot use that oxygen to breathe. There is a little bit of oxygen gas dissolved in water but unlike fish, humans cannot get it out of the water