What aspect does Henry's Law primarily focus on?

Henry's Law focuses on the relationship between gas solubility and atmospheric pressure. More specifically, it states that at a constant temperature, the amount of gas that dissolves in a liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid. This principle is particularly important in respiratory physiology because it helps explain how oxygen and carbon dioxide are transferred between the alveoli in the lungs and the blood.

The understanding of this relationship is crucial for respiratory care, as it influences how gases are administered and managed in therapeutic contexts, such as in the use of supplemental oxygen. For instance, when the partial pressure of oxygen increases, more oxygen can dissolve into the blood, enhancing oxygen delivery to tissues.

In contrast, the other options discuss different principles. The relationship between temperature and gas viscosity involves different concepts of gas behavior under varying temperatures. The relationship between gas diffusion rates and molecular weight pertains to Graham's law of effusion and does not specifically address solubility. Lastly, the interaction of gases with biological membranes includes aspects of permeability and diffusion but is separate from the specific solubility dynamics that Henry's Law addresses. This makes the understanding of gas solubility in relation to pressure a fundamental aspect in both respiratory care and general gas laws.