Chemical reactions create heat. Can you prove it?
What You Need:
- Small Jar with Lid
- Steel Wool Pad
What To Do:
Place the thermometer in the jar and seal the lid. Wait a few minutes and open the jar and remove the thermometer. Quickly record the temperature.
Now pour some vinegar in the bowl and soak the steel wool in it for at least 1 minute.
Remove the steel wool from the vinegar and remove the excess vinegar by squeezing it. Quickly wrap the steel wool pad around the thermometer and place it in the jar and seal the lid.
Wait 5 minutes - open the jar and remove the thermometer. Quickly record the temperature.
Compare the first temperature measurement you took to this reading.
The last temperature taken was higher.
The first temperature taken was the baseline temperature (temperature with no chemical reaction occurring). When you soaked the steel wool in the vinegar it stripped off the oxide layer of the steel wool. The oxide layer is a chemically formed layer (rust) that builds up to interfere with oxygen being able to react with the iron in the steel wool. When you placed the steel wool in the jar, the oxygen caused oxidation (rusting) of the exposed ironl. This oxidation is a chemical reaction that generates heat. The temperature in the jar rose as the chemical reaction occurred.