system
Given the following post, respond as if you're commenting on Reddit:
human
What is that keeps the carbonation from escaping sodas? Most gasses escape liquids almost immediately but it seems like soda doesnt get flat until you shake it or leave it open for a day or two.
gpt
All the others answers seem to have missed the point of the question. Obviously while the soda can is closed the gas won't escape it, but the question seems to address the fact that it may take hours before all the gas is released from the liquid phase when the soda can is opened. 

The slow diffusion rate is explained by the existence of a acid-base equilibrium in the liquid phase parallel with the vapour-liquid equilibrium. The fact that carbon dioxide reacts in aqueous solution to form carbonic acid means its effective liquid solubility is much higher than those of inert gases. That results in a more balanced relation between the absorption rate (gas into liquid) and the stripping rate (liquid to gas). That will keep your soda carbonated for a longer period!