Question

Assume a certain adult requires 254 mL of pure oxygen per minute. Assume inhaled air contains 20.0 percent oxygen by volume and exhaled air is 16.0 percent. (Also, assume that the volume of inhaled air is equal to that of the exhaled air.) Calculate the total volume (in liters) of air the adult breathes in a day.

Answer 1

254 ml pure O₂ requires per minute breathe.

Let us consider, volume of air per breathe = x ml.

Pure O₂ from inhaled air = 20x/100 ml and Pure O₂ from exhaled air = 16x/100 ml.

So, 20x/100 -16x/100 = 254

Therefore, x = 6350 ml

So, volume of air per minute breathe = 6350 ml.

The total volume of air the adult breathes in a day = 6350×60×24 ml

                                                                                = 9144000 ml

                                                                                 = 9144 L (Answer)