 #1
songoku
 2,130
 283
 Homework Statement:

The concentration of oxygen O2 at the atmospheric pressure is 20.9% v/v. The partial pressure of this concentration is 21.2 kPa. At an altitude of 6962 m above sea level (approximately 7000 m), what is the partial pressure of oxygen?
a. 44 kPa
b. 9.33 kPa
c. 0.21 kPa
d. 0.44 kPa
e. 21 kPa
 Relevant Equations:
 Not sure (maybe ideal gas or P = ρgh)
The pressure of oxygen at sea level = ##\frac{20.9}{100} ~\text{x} ~(21.2 ~\text{x} ~ 10^3) = 4430.8~ \text{Pa}##
Then I do not know how to calculate the pressure at altitude 7000 m. I tried using P = ρgh (taking ρ as density of air = 1.3 kg/m^{3}) then subtract the result from 4430.8 Pa but got negative result so I guess the formula I used is wrong but I do not know what other formula to use.
Thanks
Then I do not know how to calculate the pressure at altitude 7000 m. I tried using P = ρgh (taking ρ as density of air = 1.3 kg/m^{3}) then subtract the result from 4430.8 Pa but got negative result so I guess the formula I used is wrong but I do not know what other formula to use.
Thanks