Here is an interesting little side experiment from the International Space Station where and Alka-Seltzer tablet is put in to a sphere of water in zeroG. The results are actually some what surprising. The bubbles collect in the water sphere even coalescing into untimely two big ones.
Now before any one goes writing their congress men about the waste tax payer dollars, note that this in not their mission. This is the type of thing astronauts do to have a little fun after a long hard day of the real work.