A candle burns in a glass which is at least twice as high as the candle. Around the candle, we heap baking powder (sodium hydrogen carbonate) and drizzle vinegar (acid) on it.

NaHCO₃ + H₃O⁺ –> Na⁺ + CO₂ + 2 H₂O

CO₂ forms. It is heavier than air and prevents the supply of air or oxygen. The candle is extinguished.

2.

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Article Information

https:/doi.org/10.1002/chemv.201900140

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