Why oxygen tank is used for scuba diving?

Answer 1

To fit more in. If it was at 1 atmosphere of pressure it would be like breathing out of a bag. (You would run out of air in about 5 or 6 breaths) Addendum: I should add that it's not oxygen in Scuba tanks; it's air. Oxygen when delivered under pressure, can cause convulsions. You'll never see a diver with oxygen in her tanks.

The above is correct, however oxygen is used by technical divers during decompression at very shallow depths. But this is not what is in the divers main gas or bottom gas.

Answer 2

Because that is what the air that we breathe is made of. (See Below) SCUBA divers can and do make mixtures for various gases (including adding Helium - see http://www.lakesidepress.com/pulmonary/books/scuba/sectionl.htm for details) See WikiAnswer http://wiki.answers.com/Q/What_is_the_composition_of_air Nitrogen (N2): 78.09%

Oxygen (O2): 20.95%

Argon (Ar): 0.93%

Carbon dioxide (CO2): 0.038% Others (less than 0.002% each): Neon (Ne), Helium (He), Krypton (Kr), Hydrogen (H2), Xenon (Xe).

Nitrox/Trimix Nitrogen is not added to a scuba cylinder. Instead, it is simply present in air. Oxygen is added (as well as helium on occasion for a "trimix") to dilute the amount of nitrogen in a scuba cylinder. Oxygen is used since it is needed to survive as well as a decompression gas for technical divers. It is used in this case since 100% oxygen means no other gasses are being breathed - which allows other gasses built up during the dive to be eliminated faster during the breathing cycle and thus decompression time underwater can be reduced. dude... unless the questioner understands the concepts, principals and application of Partial Pressures, Decompression Theory, Oxygen Toxicity and Nitrogen Narcosis your answer is not what he is asking.

Answer 3

Nitrogen and Oxygen are present in normal air we breathe every day along with other elements. Nitrogen makes up about 78% of the air and oxygen about 20%. Other elements include argon, boron and some others but these make up about 2% between them.

Normal air is used in SCUBA tanks as it is the air we are used to breathing. This does have certain limitations in SCUBA diving and due to the high amount of nitrogen which means that the body takes on nitrogen much faster.

In response to this, some divers use special gas mixes called Nitrox which have a lower amount of Nitrogen but higher Oxygen content which in turn means that divers can get more bottom-time.

There are other gas mixes which some specialist divers use such as heliox, trimix and in some cases pure oxygen but these are all used more rarely and not so much in recreational diving

Answer 4

It's compressed so they can fit fit more oxygen in it. In face it's compressed so much that it actually turns into a liquid.