Mad About Science: Mason jar experiments

By Brenden Bobby
Reader Columnist

This article is usually written to give you answers. Today, I’m not going to give you any answers. Instead, I’m going to give you experiments and, if you really want the answers, you’ll have to experiment for yourself to get them.

These experiments are great for all ages, though parents may want to help out their children if they’re trying to avoid making a mess. All of these experiments are designed to be done inside of a Mason jar for easy containment and cleanup.

Rubber eggs

Here’s a challenge: Remove the shell from an egg without spilling or boiling it. You’ll need a Mason jar, a raw egg and some vinegar. You’ll want some food coloring or alcohol ink to really spruce up the experiment and make it your own.

Place the egg in your Mason jar, then pour in enough vinegar to completely submerge the egg. You will notice bubbles forming across the surface of the egg — what might those be? Leave the egg in the vinegar for at least 48 hours. Once you remove the egg, make note of how it has changed and what’s missing.

Want to do some more experiments on it? Shine a cat laser at it, a flashlight through it or see if it can bounce outside. Make the experiment your own.

Ocean in a jar

Have you ever wanted your own ocean? Science can help.

Courtesy illustration.

This will take a number of liquids and dyes, which we will cover as we go. You will want to mix the liquids and dyes in their own separate containers before pouring them into the Mason jar.

Your bottom layer will be corn syrup mixed with black food coloring. You will want this layer to take up about one-third of the jar. Pour it in and add a creepy squid figurine for dramatic effect. Next, you’ll want some dish soap mixed with blue or purple food coloring. It should be dark, but not as dark as the corn syrup. Next, you’ll want some water mixed with blue food coloring — use a funnel to pour it over the dish soap very slowly. It may foam up a little bit, but as long as you’re going slow, it should be fine.

Your next layer will be cooking oil; to dye it blue, you’ll need oil-based food coloring. If you know any baker friends, they might be willing to loan you some — for science! The final layer will be isopropyl alcohol. This layer requires the most finesse to put in your jar. You may want to use a dropper to slowly add the alcohol so that it doesn’t break the layer between the oil and the water.

Pop a lid on that bad boy and you’re the official owner of an ocean in a jar. Now you get to figure out why certain liquids behave differently from others, and what does and doesn’t float in your miniaturized ocean. Maybe experiment with other liquids and non-newtonian fluids and see how the experiment changes. Or you could just make a liquid rainbow jar.

Pro tip: Cut a hole in a large cork or a small piece of wood and wedge it into the top of the jar. Pop an LED bulb in the hole and you’ve created a nautical night light.

Mason jar greenhouse, root viewer

This project can be done in a number of ways. Would you like some mid-winter basil to spruce up your family sauce recipe? Maybe you’d just like to see what roots look like while a sprout is growing.

To make a functional terrarium, set a layer of small rocks across the bottom of the Mason jar. Pour some sand overtop and then a nice layer of soil. This should take up about one-third of the jar. Plant whichever seed you’d like and add water. Make sure to seal the lid on the jar, and add a nitrile glove or balloon as an airtight cover. The Mason jar should now be its own self-contained ecosystem, but if it needs more water you can pour more in before sealing it again.

How are herbs grown with this method different from the herbs from the store? Do they taste and smell better or worse?

If you just want to see how roots grow from a sprout, stuff a Mason jar with loose layers of damp paper towels. As a tip, colorful paper napkins make for a stark contrast against the roots and seeds. Seal the top and wait for the magic to happen.

Do different plants have different root systems or do they all start out the same way? Are some seeds starting better or faster than others?

Plant colorizer

This has been popularized many times over using black or blue dye in water to transform rose petals from a deep red to a chilling black or royal blue. Roses and flowers aren’t the only plants you can transform with this trick. Shockingly, one of the most effective plants you can dye is Napa cabbage, along with other large and leafy plants.

Simply mix some food coloring with water in a Mason jar and submerge the base of a plant’s stem or leaves. After a day or two, you should see a gradual color shift. In the case of a Napa cabbage leaf, you might notice the color traces vein-like lines along the structure of the leaf. Curious as to why? You’ll just have to test it on more leaves to see.

Stay curious, 7B.