Re: What liquid uses oxygen to turn blue? What is the name of this process?

        Without too much information on the chemicals used, it is 
somewhat difficult to answer this question, but I believe I have the 
answer!  The reaction you are looking for is nicknamed "the blue bottle 
reaction" essentially because the clear solution in the bottle turns blue 
when shaken, then back to clear, then blue when shaken again, etc...
        You are correct in hypothesizing that oxygen is being consumed in 
the reaction.  However, there are really a few main reactions occurring 
inside the flask (or bottle).  These reactions involve the 
following chemicals:

1.  KOH (potassium hydroxide)
2.  Glucose (a type of sugar - formula C6H12O6)
3.  Methylene Blue (a biological stain and a type of indicator - you may 
want to do a little research on indicators as there are several types that 
can tell a person different things about a solution)
4.  Water (good 'ol H2O)
5.  Oxygen (from the atmosphere)

        First, glucose reacts with hydroxide ion to form glucoside.  
(Glucoside is a fancy term for glucose that has reacted to form it's 
acetal.  Acetal is another fancy term that you probably won't need to know 
for your project, but any organic chemistry text should explain these two 
concepts.)  The hydroxide ion comes from potassium hydroxide (KOH) that has 
dissolved in water.  Just like salt dissolving in water produces Na+ and 
Cl- ions, potassium hydroxide produces K+ and OH- ions.
        When you first shake the solution, oxygen from the air is dissolved 
into the solution (just like oxygen is dissolved into a fish tank by 
pumping air into the water).  This oxygen combines with methylene blue (in 
it's reduced form) to produce the blue color of the solution (we say 
methylene blue has been oxidized).  You probably don't need to be concerned 
with the meaning of oxidation and reduction for your project.
        The glucoside formed in the first step now reacts with the oxidized 
methylene blue.  This reaction produces colorless methylene blue (the same 
colorless "reduced" form we started out with) and our friend the OH- ion, 
both of which are free to react again if the solution is shaken to 
introduce more oxygen.  The general reactions are below:

1.  KOH (dissolved in water)  --->  K+    +    OH-

2.  glucose   +   OH-   --->    glucoside

3.  O2 (gas from atmosphere)   --->   O2 (dissolved in solution)

4.      O2     +      methylene blue  --->  methylene blue
   (dissolved)         (colorless)           (color blue)
                      (reduced form)        (oxidized form)

5.  glucoside + methylene blue   --->   methylene blue   +   OH-
                 (color blue)            (colorless)
               (oxidized form)          (reduced form)

        The bubbles you see on the sides of your flask are probably just 
oxygen leaving the solution, which is why you have to shake the flask again 
to bring back the blue color.
        For more information on the chemicals used, such as chemical 
structure, density, and molecular weight, you might want to try 
www.chemfinder.com or the CRC Handbook or Merk Index, which are probably 
available at your library.  You might also want to check out these two web 
pages:

 http://www.chem.utas.edu.au/staff/yatesb/bluebottle.html

 http://chem-courses.ucsd.edu/CoursePages/Uglabs/Lecture.demos/17.html

        As a final note, there may be other chemical reactions that produce 
the same results, but I believe that this is the one you are looking for. 
Also, you noted that there were some acoustic properties to the reaction, 
but in my research I was unable to find any information on sounds produced 
by this reaction.  If you had the flask stoppered the sounds might be due 
to air escaping from or entering the flask.  This depends on the pressure 
inside the flask.  If the air was escaping quickly it probably produced a 
high pitch sound, and if it was escaping slowly it will probably have 
produced a lower sound (I'm not a physics expert, so I can't give you a 
100% accurate explanation for this).

        I hope this helps.  If you need anymore help don't hesitate to ask!

Dan Patel
dpatel9@bayou.uh.edu