The average adults takes 12 breaths in one minute, inhaling roughly 500ml of air with each breath. the molar compositions of the inspired and expired gases are as follows:

species inspired gas (%) expired gas (%)

o2 20.6 15.1

co2 0.0 3.7

n2 77.4 75.0

h2o 2.0 6.2

the inspired gas is at 24°c and 1 atm, and the expired gas is at 37°c (body temperature) and 1 atm. nitrogen is not transported into or out of the blood in the lungs, so (n2)in = (n2)out. the molar flow rate of the inspired breaths is 0.246 mol/min.

(7 points) draw a flowchart for this process and label the process streams.

(11 points) calculate the masses of o2, co2, and h2o transferred from the pulmonary gases to the bloos or vice versa (specify which) per minute.

(4 points) calculate the volume of air exhaled per ml inhaled.