Which factors increase the solubility of carbon dioxide in water?

The solubility of carbon dioxide in water is influenced by temperature and pressure. Decreasing the temperature of the water increases the solubility of gases, including carbon dioxide. This is because gases typically have lower solubility in warmer liquids; as the temperature decreases, the kinetic energy of the water molecules also decreases, allowing more gas to be dissolved in the liquid.

Increasing the temperature would have the opposite effect, reducing solubility. While stirring can help to mix the gas more thoroughly with the liquid, it does not directly affect the solubility; rather, it may speed up the dissolution process but does not increase the inherent solubility limit. Increasing the pressure of carbon dioxide above the water significantly enhances its solubility due to Henry's Law, which states that more gas dissolves in a liquid under higher pressure. However, this choice was not selected as the answer.