How does the Elephant toothpaste experiment have to do with concentration

Question

How does the Elephant toothpaste experiment have to do with concentration.

5. Add ~cont of potassium iodide solution .
6. you may touch a glowing splint to the foam
to relight it, indicating presence of oxygen.
Reaction
2 tho, (ag) – 2120117+ 02(9 )
HONDA
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