Question

Air entering the lungs ends up in tiny sacs called alveoli. It is from the alveoli that oxygen
diffuses into the blood. The average radius of the alveoli is 0.0050 cm and the air inside
contains 14 per cent oxygen. Assuming that the pressure in the alveoli is 1.0 atm and the
temperature is 37°C, calculate the number of oxygen molecules in one of the alveoli.
(a) 6x1013
(b) 10 24
(C) 1.7 x 1022
(d) 1.7 x 1012​

Answer 1

Answer:

1.759×10^12

Explanation:

Here we are given that;

Radius of alveoli = r =0.005 cm = 5×10^(-5) m

Volume of alveoli ,v = (4×3.1416×r^3) / 3 = 5.236×10^(-13) m^3

Volume of oxygen V = v×14% = 7.33×10^(-14) m^3

Pressure P =1 atm =101325 pa.

Temperature T = 37C = 310K

Formula,

Using the standard gas equation;

PV=nRT

N = (PV)/(RT)

=2.92×10^(-12) mole of oxygen

Number of oxygen = n× 6.02×10^(23)=1.759×10^12