|MadSci Network: Chemistry|
The difference between (normal, as opposed to diet) sodas -- some floating while others sink -- will be entirely due to the proportion of sugar in the soda. At a certain percentage of dissolved sugar, the density of a sealed can of soda will become great enough for it to sink in water. Other ingredients are present in amounts too small to matter. Actually your question comes as a surprise. I knew regular Coke sinks, and assumed that all sugared soda would do the same. Diet soda floats because it is mostly carbonated water (the carbonation helps reduce the density); there is much less sweetener (by weight) because aspartame is much sweeter than sugar, gram-for-gram. Dan Berger MadSci Administrator
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