Question

What will be the $p{O}_2$ and $pCO2$ in the atmospheric air compared to those in the alveolar air?

Answer 1

$p{O}_2$ higher, $pCO2$ lesser

The partial pressure of oxygen in the atmospheric air is higher than that of oxygen in the alveolar air. In the atmospheric air, $pO2$ is about 159 mm Hg. In the alveolar air, it is about 104 mm Hg. The partial pressure of carbon dioxide in the atmospheric air is lesser than that of carbon dioxide in the alveolar air. In atmospheric air, $pCO2$ is about 0.3 mmHg. In the alveolar air, it is about 40 mm Hg.