I am cooking hard-boiled eggs as I write so that we can do a quick experiment before dinner. My children will almost always drop whatever they’re doing for a fun science project. I am always thrilled to see them so enthusiastic about something that doesn’t involve screen time or sugar.
OK, the eggs are done, I just ate one, and it was delicious! Now for the experiments.
The first experiment we’ll do involves a glass bottle who’s neck is a little smaller than a hard-boiled egg, three matches, adult supervision, and the hard-boiled egg itself. It’s called Egg-in-a-Bottle. I went out to my recycling bin and discovered that my Trader Joe’s grape juice bottle is the perfect size.
The hardest part of this experiment was getting the label off of the bottle, which you don’t have to do. In fact, I’d recommend just leaving it on. Peel the hard boiled egg, set it on the bottle, and let your children verify that it won’t easily squeeze through. Then, remove the egg, light three matches and drop them into the bottle. They may not stay lit for long, but it doesn’t matter. Do it fairly quickly. I had the best luck dropping them it unlit end first. Then, simply set the egg back on top of the bottle before the matches go out and watch it be sucked in. (My matches were out just before I put the egg back on top of the bottle, and it still worked.) It’s pretty cool!
Ask your kids what they think happened. Have them draw a picture of the egg in the bottle in their science notebooks! The matches heat the air in the bottle. When the matches go out, the air rapidly cools, decreasing the air pressure in the bottle. The outside air, who’s pressure is higher actually pushes the egg into the bottle as it attempts to equalize the pressure inside of the bottle.
A fun follow-up experiment is to dissolve eggshells using vinegar. Just put two raw eggs into two juice glasses and cover them with (white or cider) vinegar. Have your kids check them the next day. The shells will have been dissolved by the vinegar, which is an acid. You might want to gently rinse the eggs with water before they handle them. Only the membrane of the egg will remain, which is like a rubbery balloon. It’s pretty neat. Have them draw or record what happened and how long it took to dissolve the shells, if they want to.
You can then pour off the vinager and cover one egg with water and the other with corn syrup. Leave them for 24 hours in the refrigerator and see what happens. Have your child record their results! From what I understand, the balloon-like membrane will let water molecules pass through and appear even more balloon-like when filled with water. I can’t wait to see what happens with the corn syrup egg. I’m guessing that the membrane may not let the corn-syrup molecules through. That’s my “hypothesis”, but I won’t know until we complete the experiment.
What is your child’s hypothesis?
Remind your children to wash their hands after handling raw eggs!
Tags: eggs, experiments, kids, Science
Creative Mama 