Demo Science

Magnetic force is one of four fundamental forces in the world. (In case you were wondering, gravity, strong atomic forces, and weak atomic forces are the other three). And magnetic fields are the forces of electrical currents and magnetic materials acting in a certain manner. Each magnet has opposing magnetic fields. These fields are polar, meaning that they have two different ends which repel each other. We call these ends North and South. (And yes, the directions North and South do relate to the Earth’s magnetic force).

Water softening is the process of removing calcium, magnesium, and other unwanted chemical and/or contaminant ions from hard water. By softening hard water, it is made more compatible with soaps; the process can also help extend the working life of plumbing by preventing the buildup of lime scale and reducing galvanic corrosion.

This is a simple, and really fun experiment that I did when I was in school. With the advent of digital, I would guess a lot of people hardly know what a film camera is, let alone how it works. But in this article, we’ll go over, briefly how film works and how to make your very own camera.

Here to There as Inefficiently as Possible!

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Let’s do a quick rundown of things all kids know about trees: they’re tall, there’s leaves at the top and roots at the bottom, they “drink” water out of the ground, they’re good for climbing and building houses in. That should pretty much cover it. If any of your students doesn’t know all of those facts, send them back down a grade and tell ‘em to come back when they’re good and learnt up.

Now, to the point of this particular Demo Science science demo: reconciling two of the above tree facts. The leaves—way, way up at the top o’ the tree—need the water that the tree drinks out of the ground to grow and continue their photosynthetic processes. But the roots that drink up that water are way, way at the bottom o’ the tree. How does the water get from the bottom to the top?

The Short Answer: Very Slowly

The water that's just reaching the leaves of these redwoods fell as rain in 1989.

The water that’s just reaching the leaves of these redwoods fell as rain in 1989.

The mechanism behind trees’ water transfer is called “capillary action.” To demonstrate this process, you’ll need two drinking glasses, something to serve as an elevated platform for one of the glasses, water with which that same elevated glass, and some paper towels. If time is not on your side, you can perform an abridged version of this experiment by exchanging the paper towels for plastic tubing. (See “The Fast Version” below.)

Fill one of your glasses to the brim with water and carefully place it onto its platform, right at the edge of said platform. (But not so close to the edge that it could fall off if bumped.) Place the empty glass on the table (or whatever is the base for your experiment) and slide it right up next to the platform so that it’s very close to, if not actually touching, the full glass.

Tear off two paper towels, twist them together into a rope kind of thing, and bend the rope-ish into a U-shape. Stick one end of your paper towel rope into the full glass, and the other end in the empty glass. Have your students observe what happens over the course of the day. This is a good place to note that this demonstration will take a while, and you may want to start it off first thing in the morning so the kids can check in on its progress multiple times throughout the day.

The Fast Version

If you don’t have all stinkin’ day to wait on a marginally-interesting science experiment, you can speed it up thusly:

Everything up to the paper towels should be the same. Then, instead of ropeifying paper towels, use a short length of plastic tube. Place one end into the full glass, then draw on the other end to start the water flowing through it. If you’ve ever siphoned anything in your life, that’s basically what you’re doing here. Put the free end of the tube into your other glass and observe as the water transfers much, much more quickly.

Note: Though faster, this version of the experiment is far less interesting, as it’s over pretty quickly. To jazz it up a little bit, I recommend putting your full glass one side of your classroom, the empty glass on the other, and getting a really long length of tube (or multiple shorter tubes joined by liquid-tight I-Flex connectors) and running it over/under/around/through any obstacles so that the water will wend its way across the room. You’ll have to put your full glass on a much higher platform this way—and it will require far more suction to start the siphoning process—but will be much more visually interesting, which is your best bet for getting today’s ADD-addled kids to pay attention to literally anything for more than three seconds at a time.

I Was Told There Would Be Science Involved…?

Whichever way you do this experiment, it’s a miniaturized and simplified version of the capillary action that a plant’s roots use to move water from the underground roots to the skyscraping leaves. All further references refer to the OG-slow-G version. (If you’re doing the fast version, just imagine everything sped up a bit.)

Before long, the end of the paper towels in the water will have soaked up enough liquid that it will start to seep down their length and into the waterless glass. In just a few minutes, water will start to accumulate in the bottom of the no-longer empty glass. It travels very, very slowly, oozing through the countless spaces between the fibers of the paper towel. Plant roots do the same basic thing, transferring water molecules between from one fiber to the next until the water has “climbed” all the way up the tree to the thirsty leaves. In your face (very slowly), gravity!

BOOM. #scienced

Photo credit: Scrubhiker (USCdyer) via Foter.com / CC BY

Don’t Burst Your Bubble

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“Bubbles, Sharon?! I’m the f*^%ing Prince of Darkness!” With those incredulous words, spoken to his wife in an episode of The Osbournes, Ozzy Osbourne gave the only acceptable argument against blowing bubbles. As for everyone isn’t part of Beelzebub’s extended family, you either enjoy blowing bubbles, or you’re a liar.

In fact, perhaps the only bad thing about bubbles is their impermanence. Wouldn’t it be rad if there was some way to make those ephemeral orbs last a little longer? With this Demo Science science demo, your students can experiment with ways to delay the bursting of their bubbles.

Authentic Small-Batch Artisanal Craft Bubble Solution

For this one, you’ll need five plastic cups (Solos work well), a bottle of liquid dish soap, some water, corn syrup, glycerin (can probably find it at your local drugstore), sugar,  lemon juice, some measuring spoons and cups, a stopwatch, a marker, and one bubble wand per student.

Start by labeling four of your cups with the additives you’ll be, um, adding to each: corn syrup, glycerin, sugar, and lemon juice. As the control, the fifth cup can be unlabeled, or you can write “soap” on it to reiterate that it’s just soap in that one.

Good job, Kevin. Now sit the hell down.

Good job, Kevin. Now sit the hell down.

Pour precisely one cup of water into each cup, then add about three tablespoons of dish soap to each and stir ‘em up a bit. Let your students know that the additives are the independent variable here—which one will make the bubbles last longest?—and that you’ll be comparing and contrasting the results you get from each. (Write that down, Kevin.)

Add precisely three teaspoons of the appropriate additive to each of your labeled cups and mix the solutions again. Either man the stopwatch yourself, or pass it off to your most reliable student; the stopwatcher will be timing how long bubbles last before they burst, as well as recording the results. Have the rest of your students debate which additive will yield the best results, then divide them into five groups, one for each cup.

Starting with the control solution (“soap”), have one kid dip in his/her bubble wand and blow the mightiest bubble they can. Your stopwatcher should start the timer as soon as the bubble breaks free of the wand, and stop it as soon as the bubble pops, then record the time and bubble solution used. Rotate through the groups, one kid at a time, until each student has had at last one bubble lifespan recorded. (Bubbles that hit something and burst, rather than just floating around and popping on their own, should not be counted in the results; have those students reblow a new bubble until the desired result is achieved.)

When all bubbles have been blown, have your students figure out the average time the bubbles of each different solution lasted. What are their findings?

And The Best Bubbles Be…?

Chances are better than good that the glycerin bubbles lasted the longest, since most commercially-available bubble solutions are made from water, detergent, and glycerin. This thick, clear, odorless substance is a byproduct of most soap-making processes, and, in this case, forms a bond with the hydrogen in the water to help delay evaporation (which is what causes untouched bubbles to burst).

However, science being the fickle beast that it is, it’s entirely possible that your experiment may yield different results. If so, ask your students what they think helped the winning formula outlast the glycerin bubbles. They’ll all be wrong, probably, but you’ve got to start somewhere.

BOOM. #scienced

Photo credit: JohnGoode via Foter.com / CC BY

The Science of Magic* Crystals

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We all know crystals can grant magical healing and seeing-the-future powers. That’s a no brainer. We all also know that it has to be just the right kind of special crystal, though, in order to imbue the user with these powers. It can be difficult or impossible to determine which crystals will impart these powers, though—you can’t just grab any crystal you find on the street and start curing cancer!

Rather than fumble and bumble about trying to find a magic crystal, I suggest growing your own crystals and keeping your fingers crossed that one of them will turn out to be magical. You’ve got a whole classroom full of students at your disposal, so you can have them each grow their own crystal and multiply your chances for magicalness by, um, however many students you have. It’s easy!

Behold! The saltiest of crystals

Behold! The saltiest of crystals

Grow Like Magic*

For this Demo Science science demo, you’ll need a jar for each student, a half cup of salt for each student (good thing salt is dirt cheap!), spoons, string, at least one scissor, a mess of toothpicks, and a good amount of water.

The actual experiment itself is really pretty simple. Have each kid pour about a half cup of salt into his or her jar, then fill it the rest of the way with water (not totally full, you need a little room to work, so leave some room at the top). Pass the spoons around so everyone can stir up their salt-and-water mixture to turn it into saltwater.

Cut a length of string for each student; if any of them can be trusted with a scissor, they can help you cut the string. Have everyone tie their bit of string to a toothpick, then have them plop the strings into their jars, with the toothpicks hanging over the side.

Then, we wait…

Patience is A Virtue, Kids

You’ll have to leave this one for a while, possibly several days. Some strings may start to “grow” their crystals sooner than others—those kids get bonus points. Eventually, though, everyone should have a nice little string of salt crystals. Take them out of the jar when the time is right and examine them under a microscope or microscopes. (Oh yeah, you also need as many microscopes as you can round up for this science experiment. Add that to the list above.)

What do your students see when inspecting their crystal strands? Under magnification, they should be able to see the structure of the individual crystals pretty clearly. What shape are the crystals? What color? Are there any living microorganisms mixed in? (This is entirely possible, depending on what might be in the water and/or salt, but not guaranteed to happen.) Are they groupings of a bunch of smaller crystals? Or just a few larger crystals?

There’s a lot that can be learned from just lil’ ol’ water and salt. With any luck, at least a quarter of them will impart magical powers. Don’t let your students know that, though, or all heck will break loose!

BOOM. #scienced

* Magic not guaranteed.

Photo credit: Ellyll via Foter.com / CC BY-NC-SA

A Big Ol’ Bottle o’ Tornado!

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Though not as big or as long lasting as hurricanes, tornadoes are still pound-for-pound the most destructive force on Earth. They bring naught but unbelievably high-speed winds to the party, and can easily plow through anything that gets in their path. Those mighty, swirling winds form a vortex as they go, but with all the havoc they wreak, it can be difficult for the average Joe to get a good look at that well-known funnel-like form.

This handy dandy Demo Science science demo makes it easy for your students to see just what a vortex looks like and how the materials in that vortex move. Let’s take this one for a spin!

Make That 2 Bottles

For this experiment, you’ll need two two-liter soda bottles (no, one four-liter bottle will not work, Kevin!) with their caps, an electric drill and 1/2” drill bit, some duct tape, a little caulk (that’s c-a-u-l-k caulk, wiseguy), water, food coloring, and plastic confetti (or similar).

First things first, empty your soda bottles in whatever manner you see fit. Drink ‘em at home, bring ‘em in for the students to share (don’t give any to Kevin—his mom insists he’s “allergic” to sugar), pour ‘em down the drain, whatever. Just empty those suckers, then rinse ‘em clean and dry the outsides—the insides can still be wet.

Drill a hole in the center of each bottle cap, then stack them up back-to-back (top-to-top?) and seal the outer edge with a bead of caulk. Whatever you do, don’t eat caulk—you’ll just get sticky goo all over your face. Let your caulk dry, then wrap a few strips of duct tape around the double cap for an extra tight seal. (Alternatively to all this rabble, you can buy one of these suckers.) Screw your completed cap contraption onto one of the bottles.

Fill the other bottle about 3/4 of the way full with water. Add your food coloring (any color will work, but lighter colors seem to “show up” better in this experiment), as well as your plastic confetti. Then, connect the empty bottle to the filled bottle via the double cap thing.

Now, hold your double bottle by the neck (over the duct tape) with one hand, and place your other hand on the bottom of the filled bottle. Swirl the whole thing around in a circle, as vigorously as is reasonable. Then, flip it so the filled bottle is on top and continue to swirl a few more times. Set the bottles carefully on your desk and continue hold onto the top bottle to prevent it from tipping over.

Good job, Kevin. *heavy sigh*

Good job, Kevin. *heavy sigh*

Give Me Vortex or Give Me Death

If you did it right, the water will form its own tornado-esque spinning vortex as it drains from the upper bottle into the lower. The confetti, of course, represents debris caught up in the whirling dervish of death and destruction. Your students can now get a look at the structure of a tornado without risking life and limb.

BOOM. #scienced

Photo credit: ARM Climate Research Facility via Foter.com / CC BY-NC-SA

1 Part Lamp, 1 Part Lava

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I will readily admit that this particular science project is not all that sciencey. There’s not a whole lot to really learn from this one, in the grand scientific scheme of things. But I feel that, if you haven’t made a DIY “lava lamp” with your students at least once, you’ve failed—not only the students, but yourself. So don’t complain about the lack of “real” science in this one and just get out there and do it because it’s your duty as an American educator in 2016. (Please note, if you’re not teaching in America, you are not obligated to do this one. Still, it’s a fun one, so maybe give it a shot.)

Demo “Science”

lava lamp

Please note that you will not be construction anything that close to an actual lava lamp. There will be no electricity involved, no wiring, no light bulbs, etc. This experiment simply mimics the look of a lava lamp in action.

For this Demo Science science-adjacent demo, you’ll need an empty two-liter soda bottle (how you empty that bottle is up to you, but DO NOT give Kevin any soda—his mom will figuratively kill you), about 3/4 cup of water, some vegetable oil, Alka Seltzer or other similarly fizzy tablets, and food coloring. A funnel might also be helpful. If you want to concoct a lava lamp for each student, obviously multiply your supplies by however many kids are in your class.

First, once the bottle is nice and clean, pour in the water. Then, slowly pour the veggie oil into the bottle (this is where the funnel comes in handy) until the bottle is nearly full. Chillax for a few minutes as the water and oil separate, which they will do automatically.

Splorp in about 10 drops of food coloring—any color is fine, but note that yellow won’t show up all that well. The food coloring will pass right through the oil and mix with the water. Once that’s all nice and mixy mixy, break an Alka Seltzer (or whatever you’re using) in twain and drop it into the bottle. As it sinks to the bottom and reacts with the water, the lava lamp-esque action will begin.

Stick a flashlight under that sucker to give more of a “real” lava lamp look. Drop in another Alka Seltzer to keep the blobs a bubblin’ and the bubbles a-blobbin’.

BOOM. #scienced?

Photo credit: Mike Licht, NotionsCapital.com via Foter.com / CC BY