Scuba diver helium used

The gas is also used to fill balloons, in gas discharge lamps, and as an additive in the breathing gases of astronauts and scuba divers. The rarer stable isotope of helium (3He) is produced by the decay of radioactive tritium, and is used in resonance imaging and in the attainment of very low temperatures, about 0.010 kelvin, via a process known as dilution refrigeration. see also Noble Gases Nuclear Fusion. 

Scuba divers use a mixture of helium and oxygen in their tanks. What is the pressure of the oxygen in a tank if the pressure caused by the helium is 200 torr and the total pressure in the tank is 925 torr ... 

Scuba diving The Increased pressure that scuba divers experience far below the water s surface can cause too much oxygen to enter their blood, which would result in confusion and nausea. To avoid this, divers sometimes use a gas mixture called heliox—oxygen diluted with helium. Helium s high ionization energy ensures that it will not react chemically In the bloodstream. 

Scuba divers breathe a compressed mixture of gases. For shallow recreational diving, compressed air is generally used. For dives to greater depths, various mixtures of helium, nitrogen, and oxygen are used. 

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