source: B.Z. Shakhashiri, "Chemical
Demonstrations: A Handbook for Teachers" (University of Wisconsin,
Wisconsin, 1985), and R.J. Field, "A Reaction Periodic in Time and
Space", J. Chem. Ed. 49, 308 (1972). Also see J.A. Pojman,
R. Craven, D.C. Leard, J. Chem. Ed. 71, 84 (1994) for a description
of a Physical Chemistry Lab experiment.
Prepare a solution with the following concentrations of reactants. The volume should be large enough for the intendended audience to view. The reaction mixture should be stirred constantly with a magnetic stirring bar. These concentrations will give a system that oscillates with a period of about 30 sec and the oscillations will continue for 50 minutes or more. The reactants can be mixed in any order.
|
Reactant |
Concentration, M |
|
Ce(NH4)2 (NO3)5 (catalyst) |
0.002 |
|
CH2 (COOH)2 |
0.275 |
|
KBrO3 |
0.0625 |
|
H2SO4 |
1.5 |
|
Ferroin (indicator) |
0.0006 |
return to contents , see other
references .