Posted by Standard C. on .
an athlete has a large lung capacity of 7.0L. Assuming to be an ideal gas how many molecules of air are in the athletes lungs when the air temperature in the lungs is 37 degrees celcius under normal atmospheric pressure.

physics 
drwls,
Calculate the number of moles, n, using
n = P V/(RT)
and multiply n by Avogadro's number.
T = 310 K
R = 0.08206 literatm/moleK
P = pressure in atm
V = volume in liters
You many have seen other values of R that are used with SI units (m^3 and N/m^2). The value above will save you time doing the calculation.
It is also handy to remember that 1 mole of gas occupies 22.4 liters at 0 C (273 K) and 1 atm. You have
(7.0/22.4)*(273/310) = 0.275 moles 
physics 
Anonymous,
The capacity of lung in adult 500ml and mornal body temprutere37°cand one atomsphere pressure how moles full the lung