At a depth of 80 fsw/24.4m, what is the pN2 of the air Kevin inhales?

To determine the partial pressure of nitrogen (pN2) at a depth of 80 feet of seawater (fsw), it's essential to apply the principles of gas laws, particularly Dalton's Law of Partial Pressures.

At 80 fsw, the absolute pressure can be calculated by adding the pressure of the water column to the atmospheric pressure at the surface. The pressure exerted by the water column (in atmospheres) can be calculated as follows:

1. Calculate the pressure due to water: The weight of seawater can be approximated at about 0.445 psi per foot. Therefore, at 80 fsw, the pressure from the water column will be approximately:

[

80 , \text{fsw} \times 0.445 , \text{psi/fsw} \approx 35.6 , \text{psi}

]

2. Add the atmospheric pressure: The standard atmospheric pressure at sea level is about 14.7 psi. Thus, the total absolute pressure at 80 fsw is approximately:

[

35.6 , \text{psi} + 14.7 , \text{