Question

The volume of air taken in during a typical breath is 0.47 L. The inhaled air is heated to 37∘C (the internal body temperature) as it enters the lungs. Because air is about 80% nitrogen, N2, model it as an ideal gas.

Suppose that the outside air is at room temperature (17.0∘C) and that a person takes two breaths every 3.0 s. Assume that the pressure does not change during the process. How many joules of heat Q1does it take to warm the air in a single breath?

Q1= ____ J

If the typical daily caloric intake is 2700 kcal per day, what percentage P of this caloric intake is used in heating the air the person breathes?

P = _____%

Answer 1