Ever notice your diet sodas floating to the top of your cooler when the full flavors just chill at the bottom?

Reddit user Sevlins explains:

Because “Sugar is denser than sweetener” is sort of right, here’s the actual answer:

Sugar/Water solution is denser than pure water. Artificial sweeteners however are hundreds time more potent per gram than sugar is. This means that diet soda’s Sweetener/Water solution is density wise very close to that of water since so little sweetener is needed.

The small amount of gas in the can is enough to make the can buoyant for Sweetner/Water solution, but is not enough to overcome the density of the Sugar/Water solution.

Now what about light beer vs. heavy?