At saturation, what happens to the pressure of the dissolved gas?

At saturation, the pressure of the dissolved gas in a liquid equalizes with the gas pressure above that liquid. This is based on the principle of Henry's Law, which states that the amount of gas dissolved in a liquid is proportional to the partial pressure of that gas in equilibrium with the liquid. When a gas is saturated in a liquid, the molecules of the gas dissolved in the liquid are in balance with the gas molecules in the gaseous phase above the liquid. As gas molecules exit the liquid, new molecules enter until a state of equilibrium is reached, meaning the pressure of the dissolved gas matches the pressure of the gas present in the environment.

In this context, other answers may suggest various changes in pressure, but they do not accurately reflect the concept of saturation. For instance, decreasing pressure of dissolved gas would indicate that the gas is less soluble, which doesn't occur at saturation. Similarly, stating that the pressure increases significantly or becomes negligible does not align with the definition of the state of saturation, which maintains a balance between the liquid and gas phases.