Have you ever opened a jar of pickles? No? Don't have any pickles? Oh well. Just imagine you are opening a jar of pickles right now.

(We here on the Aspire staff are really hungry right now. We here on the Aspire staff are actually drooling.)

Anyway, if you were to open a fresh jar of pickles right now, you would hear a pop as the "freshness button" popped up. Then you would smell sweet, wonderful green pickles, the kind of pickles that we here on the Aspire staff really, really wish we had right now. But nooooooo! We have to keep on working and slaving away! Do we get any breaks? No, no breaks for us here on the Aspire staff! But do we complain? Yes. Very often.

Excuse us, we got side-tracked.

Do you know why that button pops up when you open the jar, and then never goes back down? Discuss this with your lab partner and record your explanation in the lab packet.


Here's a hint:
It has to do with the gases inside the jar.
Here's a better hint: When pickles are put in their jars, the jars, their juices, and the pickles are steaming hot. (Ever played hot pickle? It's fun.) When you buy your pickles, they are at room temperature.
Hmmmm. Sounds like a job for (dum dum da daa) Experiment Man! Or Woman!

Let's start to set up our experiment by noting what we know about our pickle puzzle.

  1. Inside the jar, along with the pickles and the pickle juices, there is a small volume of (gas) air.

  2. While the pickles are being canned, the pickle jar is heated up until it is pretty hot. Then the hot pickles are put in the jar and the lid is closed tightly. The button on the top of the lid is in the "up" position.

  3. Now the pickles are left to cool.

  4. The next day, the button on top of the jar is in the "down" position.

  5. The jar stays the same size.

Probably we'd better use an experiment that will help us to understand how pockets of gas behave when they are heated and cooled.

Back to the lab menu... On to the lab activity...

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