Does coke or diet coke float?

Diet Coke floats because Floating occurs because floating objects displace, or push aside, a certain amount of liquid. If an object displaces more than its weight in liquid, it floats; otherwise it sinks.

Density (the mass per unit of volume) determines how much liquid is displaced. Density is usually compared to water, which is assigned a density of 1. Materials sink if (like regular Coke) they are more dense than water, while less-dense materials, like Diet Coke, float.