Question

During a normal breath, our lungs expand about 0.50 L against an external pressure of 1.0 atm. How much work is involved in this process (in J)?

a) 0.50 J
b) 1.0 J
c) 0.50 atm L
d) 0.50 J/atm

Answer 1

The work involved in a normal breath when the lungs expand 0.50 L against a pressure of 1.0 atm is calculated to be 0.50 L•atm. This is equivalent to 50.65 joules.

Step-by-step explanation:

The student is asking about the work done by the lungs during a normal breath when expanding against an external pressure. To calculate this, we can use the formula work = pressure × volume change. Given that the lungs expand about 0.50 L against an external pressure of 1.0 atm during a normal breath, we can find the work in liter-atmospheres (L•atm) before converting it to joules (J). Since 1 L•atm is equivalent to 101.3 J, the work done in a normal breath is:

Work = 1.0 atm × 0.50 L = 0.50 L•atm

Converting this to joules:

Work = 0.50 L•atm × 101.3 J/L•atm = 50.65 J