Thermodynamics Entropy CIA Demonstration: Copper ... - Cengage

Thermodynamics Entropy CIA Demonstration: Copper-Catalyzed Decomposition of Acetone Page [1 of 1] 3108 – CIA Demonstration: Copper-Catalyzed Decomposi...

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Thermodynamics Entropy CIA Demonstration: Copper-Catalyzed Decomposition of Acetone Page [1 of 1] 3108 – CIA Demonstration: Copper-Catalyzed Decomposition of Acetone

What I have here is a 1962 penny. 1982 is when we switched from copper pennies to copper and zinc pennies. And what I’m doing is I’m heating it up in a Bunsen burner flame and then I’m going to hang it on the edge of a beaker that has some acetone in the bottom of it. And with the lights on, you can see that it becomes very coppery colored and you can almost see the waves of acetone wafting over the penny. The penny is catalyzing the decomposition of acetone to ketene and that’s an exothermic and so it’s the exothermicity – the heat that is liberated – that’s keeping the penny hot. Now, it looks okay when we’ve got the lights on, but let’s turn the lights off now, please, and you’ll see how dramatic it is. Again, the penny is sort of red-hot. The energy that is being delivered to it to keep it red-hot is from the partial oxidation of acetone to ketene using as the oxidant.