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Belousov-Zhabotinskii Reaction (classic)

Solutions

• Solution A:    0.23M KBrO₃
• Solution B:    0.31M malonic acid
  0.059M KBr
• Solution C:   0.019M Ce(NH₄)₂ (NO₃)₆
  2.7M H₂SO₄
• Solution D:    0.025M ferroin sulfate

Procedure

1. In a 1 liter flask, add 300ml solution A to 300ml solution B. Solution becomes amber.
2. Wait until the solution clears, add 300ml solution C, mixture turns orange with the smell of bromine.
3. Wait until the orange color fades to the yellow cerium solution color and add 3.6ml solution D.
4. Color changes from gorgeous green to pompous purple to rusty red to blink of blue (if you blink you miss the blue) and finally back to gorgeous green. Cycle takes ~1 min, with the cycle lengthening with time.

Disposal

To dispose, neutralize the solution with sodium bicarbonate and pour it down the drain.