Percentage of oxygen at 10000 feet level?

Answer 1

The percentage of oxygen in the atmosphere does not change with altitude, so it is about 21% at 10 000 feet. What does change is the pressure. This declines with altitude. At sea level the air pressure is about 101 kPa (kilopascals). Oxygen accounts for 21% of this so the oxygen pressure is 19.6 kPa. This means that there are less oxygen molecules in the same volume of air at higher altitudes. At 10000 feet the oxygen pressure drops to 7.2 kPa, which is roughly one third of the pressure at sea level. For an online calculator of oxygen levels at different altitudes see: http://www.altitude.org/calculators/oxygencalculator/oxygencalculator.htm This site also lets you convert between kilopascals and mm Hg. For further information about the effects of altitude see: http://anthro.palomar.edu/adapt/adapt_3.htm http://www.bmj.com/cgi/content/full/317/7165/1063