What does Henry's law explain regarding gas absorption?

Henry's law explains that the amount of gas that can dissolve in a liquid at a certain temperature is directly proportional to the partial pressure of that gas above the liquid. This means that when the breathing gas is at a higher pressure, more gas molecules will be forced into solution in the body's tissues and fluids. In the context of diving, as a diver descends and experiences increased water pressure, the surrounding pressure on the gases increases, leading to a greater absorption of the breathing gas into the blood and body tissues. This principle is critical for divers to understand, as it relates directly to the risks associated with decompression sickness, or "the bends," when returning to the surface and experiencing lower pressures.

The other options do not accurately capture the relationship outlined in Henry's law. Gases do not dissolve in liquids at a constant rate regardless of pressure, nor does increasing temperature generally increase gas solubility—often it decreases it. Liquid depth does correlate with gas absorption due to the changes in pressure, contradicting the notion that depth has no effect on gas absorption.