Question

People breathe. Calculate the number of moles in the 2.1 L volume of air in the lungs of the average person. Note that the air is at 37°C (body temperature)

Answer 1

Given:

• Volume of air in lungs = 2.1 L

,

• Temperature of air = 37°C

Apply the equation of ideal gas law:

$PV=nRT$

Rewrite the equation for n:

$n=\frac{PV}{RT}$

Where:

• P is the pressure = 1.013 x 10⁵ N/m²

,

• V is the volume in m³ = 2.10 x 10⁻³ m³

,

• R is the gas constant = 8.31 J/mol .K

,

• T is the temperature in kelvin

,

• n is the number of moles of atoms.

Now, convert the temperature to Kelvin:

$T=37^oC+273.15k=310.15\text{ k}$

Now, substitute values into the equation and solve for n:

$n=\frac{(1.013*10^5)*(2.10*10^{-3})}{8.31*310.15}$

Solving further:

$\begin{gathered} n=\frac{212.73}{2577.3465} \\ \\ n=0.0825\approx8.25\times10^{-2\text{ }}mol \end{gathered}$

Therefore, the number of moles is 8.25 x 10⁻² mol

ANSWER:

8.25 x 10⁻² mol.