Tag: STEM’

Holiday Science: Candy Cane Art

 - by KitchenPantryScientist

Crying over broken candy canes? Cry no more. Make art!

Candy Cane Art- image KitchenPantryScientist.com

Candy Cane Art- image KitchenPantryScientist.com

My publisher recently sent me a copy of “Amazing (Mostly) Edible Science,” by Andrew Schloss. There are tons of fun experiments in the book, but Candy Cane Origami seemed like a perfect one to try during the holidays.

*Melted candy can get dangerously hot, so parental supervision is required!

You’ll need:

-candy canes (broken or whole), wrappers removed

-heavy-duty aluminum foil

-a cookie sheet

-a wire cooling rack

-an oven

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What to do:

  1. Preheat oven to 250F.
  2. Cover cookie sheet with foil
  3. Place candy canes on foil, not touching each other
  4. Bake candy canes for around 10 minutes and have an adult check them. They should be stretchy, but not too hot to touch.img_5761
  5. When the candy canes are ready, bend, fold, twist and pull them into cool shapes. Try pulling one long and wrapping it around a chopstick to make a spiral. What else could you try?
  6. If the candy gets to brittle to work with, put it back in the oven for a few minutes to make it soft again.
Candy Cane Art- image KitchenPantryScientistcom

Candy Cane Art- image KitchenPantryScientistcom

The science behind the fun:

If you looks at the ingredients of candy canes, they’re usually made of table sugar (sucrose), corn syrup, flavoring, and food coloring. Glucose and fructose are sweet-tasting molecules that stick together to make up most of the sugars we eat, like table sugar (sucrose) and corn syrup. You can think of them as the building blocks of candy.

At room temperature, candy canes are hard and brittle, but adding heat changes the way the molecules behave. Both table sugar and corn syrup contain linked molecules of glucose and fructose, but corn syrup has much more fructose than glucose, and the fructose interferes with sugar crystal formation. According to Andrew Schloss, “the corn syrup has more fructose, which means the sugar crystals in the candy don’t fit tightly together. The crystals have space between them, which allows them to bend and move without cracking.

Here’s a great article on the science of candy-making!

If you’re looking for holiday gifts for a science-loving kid, my books Kitchen Science Lab for Kids and Outdoor Science Lab for Kids include over 100 fun family-friendly experiments! They’re available wherever books are sold.

Think #STEAM! Homemade Holiday Window Stickies

 - by KitchenPantryScientist

 

Gelatin is the substance that makes Jell-O jiggle. See what happens when food coloring molecules move, or DIFFUSE through Jell-O.

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This creative science experiment that my kids and I invented lets you play with floatation physics by sprinkling glitter on melted gelatin, watch colorful dyes diffuse to create patterns and then use cookie cutters to punch out sticky window decorations.  Water will evaporate from the gelatin, leaving you with paper-thin “stained glass” shapes.

You’ll need

-plain, unflavored gelatin from the grocery store or Target

-food coloring

a drinking straw

-water

-a ruler

-glitter

*You can use the recipe below for two pans around 8×12 inches, or use large, rimmed cookie sheets for your gelatin. For a single pan, cut the recipe in half.

Step 1. Add 6 packs of plain, unflavored gelatin (1 oz or 28 gm) to 4 cups of boiling water. Stir well until all the gelatin has dissolved and remove bubbles with a spoon.

Step 2. Allow gelatin to cool to a kid-safe temperature. Pour the liquid gelatin into two large pans so it’s around 1-1.5 cm deep. It doesn’t have to be exact.

Step 3. Sprinkle glitter on the gelatin in one pan.  What happens?
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Step 4. Allow the gelatin to harden in both pans.

Step 5. In the pan with no glitter, use a straw to create holes in the gelatin, a few cm apart, scattered across the surface. It works best to poke a straw straight into the gelatin, but not all the way to the bottom. Spin the straw and remove it. Then, use a toothpick or skewer to pull out the gelatin plug you’ve created. This will leave a perfect hole for the food coloring. Very young children may need help.
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Step 6. Add a drop of food coloring to each hole in the gelatin.
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Step 7. Let the gelatin pans sit for 24 hours. Every so often, use a ruler to measure the circle of food coloring molecules as they diffuse (move) into the gelatin around them (read about diffusion at the bottom of this post.)  How many cm per hour is the color diffusing?  Do some colors diffuse faster than others? If you put one pan in the refrigerator and an identical one at room temperature, does the food coloring diffuse at the same rate?

Step 8. When the food coloring has made colorful circles in the gelatin, use cookie cutters to cut shapes from both pans of gelatin (glitter and food coloring), carefully remove them from the pan with a spatula or your fingers, and use them to decorate a window. (Ask a parent first, since some glitter may find its way to the floor!) Don’t get frustrated if they break, since you can stick them back together on the window.
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Step 9. Observe your window jellies each day to see what happens when the water evaporates from the gelatin.
IMG_3688When they’re dry, peel them off the window. Are they thinner than when you started? Why? Can you re-hydrate them by soaking the dried shapes in water?
IMG_3691The Science Behind the Fun:

Imagine half a box filled with red balls and the other half filled with yellow ones.  If you set the box on something that vibrates, the balls will move around randomly, until the red and yellow balls are evenly mixed up.

Scientists call this process, when molecules move from areas of high concentration, where there are lots of other similar molecules, to areas of low concentration, where there are fewer similar molecules DIFFUSION. When the molecules are evenly spread throughout the space, it is called EQUILIBRIUM. 

Lots of things can affect how fast molecules diffuse, including temperature.  When molecules are heated up, they vibrate faster and move around faster, which helps them reach equilibrium more quickly than they would if it were cold. Diffusion takes place in gases like air, liquids like water, and even solids (semiconductors for computers are made by diffusing elements into one another.)

Think about the way pollutants move from one place to another through air, water and even soil. Or consider how bacteria are able to take up the substances they need to thrive. Your body has to transfer oxygen, carbon dioxide and water by processes involving diffusion as well.

Why does glitter float on gelatin? An object’s density and it’s shape help determine its buoyancy, or whether it will float or sink. Density is an object’s mass (loosely defined as its weight) divided by its volume (how much space it takes up.) A famous scientist named Archimedes discovered that any floating object displaces its own weight of fluid. Boats have to be designed in shapes that will displace, or push, at least as much water as they weigh in order to float.

For example, a 100 pound block of metal won’t move much water out of the way, and sinks fast since it’s denser than water. However , a 100 pound block of metal reshaped into a boat pushes more water out of the way and will float if you design it well!

What is the shape of your glitter? Does it float or sink in the gelatin?

Here’s a video I made for KidScience app that demonstrates how to make window gellies

Credit: My 11 YO daughter came up with the brilliant idea to stick this experiment on windows. I was just going to dry out the gelatin shapes to make ornaments. Kids are often way more creative than adults!

Rubber Band Car

 - by KitchenPantryScientist

It’s fun to make a rubber-band powered car from cardboard, straws, and wooden skewers!

You’ll need:

-heavy cardboard

-rubber bands

-glue (a glue gun works best)

-a plastic straw

-wooden skewers

-a CD (or a compass)

-a ruler

-screwdriverCu

-pipe cleaner (optional)

Hints: Parental supervision recommended for hot glue gun use.

Here’s what you’ll be building:

Rubber Band Car kitchenpantryscientist.com

What to do:

  1. Wrap cardboard around a large spice bottle so you can see how it bends. Cut a piece of cardboard about 9 inches (22cm) long to wrap around the bottle. Trim off the excess cardboard and tape it to create a tube.

    kitchenpantryscientist.com

  2. Trace a CD or use a compass to make 8 circles that are around 4 and 1/2 inches (12 cm) in diameter. Use a ruler to make a square around each circle and then diagonal lines to mark the center of each circle. Cut them out and glue two circles together until you have four wheels. Use skewers to poke holes through the center of each wheel.

    kitchenpantryscientist.com

  3. Poke skewers through each end of the cardboard tube, about 1 and 1/2 inches (4 cm) from the end of each tube. Make sure that the skewers are parallel and that they line up when you look through the end of the tube.

    kitchenpantryscientist.com

    kitchenpantryscientist.com

  4. Use a screwdriver to make the holes larger.

    kitchenpantryscientist.com

  5. Cut 4 pieces off of a straw that are about 1/2 inch (1.5cm) long. Glue them to the outside of each hole in the tube. Use a skewer to help align them. The skewer should spin freely.

    kitchenpantryscientist.com

  6. One at a time, put wheels on the skewers and glue the OUTSIDE of the wheel to the skewer. Make sure that the wheels are parallel to the car, and to each other as they dry. Cut off excess skewer.

    kitchenpantryscientist.com

    kitchenpantryscientist.com

  7. Poke a skewer down the center of one end of the car, parallel to the wheels so that it’s sticking out about 1 inch (3 cm.) See image above.
  8. Decorate the car!
  9. Tie three thin rubber bands together and hook them over the skewer that’s sticking out. If you have a pipe cleaner or wire, hook it onto the other end of the rubber bands. Drop the rubber bands down through the center of the tube.

    kitchenpantryscientist.com

  10. Grab the rubber bands from the end opposite where they are attached to the car. Remove the pipe cleaner hook and wind them around the skewer to create tension in the rubber bands. Wind them until they’re tight.

    kitchenpantryscientist.com

  11. Set the car down and let the wheels start to spin to see what direction the car will go. When you’re ready, let go!
  12. Measure how far the car traveled.

Enrichment: How can you make the car go faster or farther. Try using different kinds and numbers of rubber bands. How could you redesign the car to make it work better?

The Science Behind the Fun:

In this experiment, you use your body’s energy to twist rubber bands around the wooden skewer axle of a cardboard car. The energy is stored as elastic energy in the tightly-stretched rubber bands. When you let the car go, the rubber bands apply enough force on the axle to turn the wheels on the car and elastic energy is transformed into the energy of motion, which is called kinetic energy.

 

Bristlebots

 - by KitchenPantryScientist

With a brush, some batteries, a small motor and a few wires, it’s easy to create a robot that spins, bumps and buzzes around on any smooth surface.

You’ll need:

-a small brush, like a vegetable brush or a cleaning brush

-two AA batteries

battery holder for 2 AA batteries (optional)

-insulated wire

-a small toy motor with lead wires and pencil eraser or small rubber stopper (or vibrating motor)

battery clip (optional)

-zip ties (optional)

-electrical tape or duct tape

Bristlebot-KitchenPantryScientist.com

Make your bristlebot!

  1. Attach the motor to one end of the top of the brush. If it’s not a vibrating motor, stick a eraser or rubber stopper onto the spinning post to make it vibrate. Use a zip tie or duct tape to secure it. Make sure the spinning parts can rotate freely.

    Attach motor- KitchenPantryScientist.com

  2. Attach the battery holder to the top of the brush near the motor.

    Attach batteries- KitchenPantryScientist.com

  3. Insert batteries in motor.
  4. Twist wires around the motor terminals and secure with tape. (These may be the wires on the battery clip, if you have one.)

    Connect battery clip- KitchenPantryScientist.com

  5. To start the motor, attach wires directly to the battery terminals, or to the battery clip and snap it onto the batteries.

    Bristlebot- KitchenPantryScientist.com

  6. Place your robot on a smooth surface to see what happens.

Enrichment: Try different brush shapes, sizes and angles to see how they move. Does your robot spin in the same direction as the motor, or the opposite direction?

The Science Behind the Fun: In this experiment, you complete a battery-powered electrical circuit to spin a vibrating motor. The vibrations traveling through the bristles of the brush move your robot around on the floor.

 

 

 

 

Graphite Circuits

 - by KitchenPantryScientist

Electrons (negatively charged particles) can flow through substances called conductors.

Graphite, used to make pencil lead, among other things, is a conductor and can be used to make a simple circuit on paper. A circuit is just a path for electrical current.

You have to do this experiment with a graphite pencil, rather than the kind you use at school, but you can pick them up at most art supply stores. You’ll also need a few small LED bulbs, 2 wires with alligator clips on either end, and a 9 volt battery.

Adult supervision recommended.

  1. Make a thick, black rectangle using a graphite pencil. We used a #9 graphite crayon.
  2. Hook the two wires up to the battery terminals.
  3. Clip the wire attached to the positive battery terminal to one wire of an LED bulb. (Don’t test it on the battery, or you may blow it out.)

IMG_58434. Touch the un-attached LED wire to the other (left) side of the graphite bar.

IMG_58445.Touch the alligator clip attached to the negative battery terminal to the right side of the graphite bar you drew.

6.If it doesn’t light, switch the positive alligator clip to the other wire of the LED bulb and try it again.

7. Move negative clip closer to the bulb. It should get brighter as you decrease the distance.

 

Electroscopes and Static Electricity

 - by KitchenPantryScientist

Repost from Dec.19th, 2010 (Photos from Kitchen Science Lab for Kids, Quarry Books 2014)

Have you ever gotten a shock from a doorknob after shuffling across a carpet? The term “static electricity” refers to the build-up of a positive or negative electrical charge on the surface of an object.  In this case, the charged object is your body.  You feel an electric shock as the charge you’ve collected from the carpet jumps from your hand to the metal doorknob.

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Tiny particles called electrons have negative charges and can jump from object to object. When you rub a balloon on your hair, or a comb through it, many of these electrons are stripped from your hair and move to the balloon or comb giving it a negative charge (and often leaving your hair all positively charged and standing up as the strands try to avoid each other.)

The negatively charged balloon or comb then makes a great tool for making electrons jump around!

You can easily make a contraption called an electroscope using:

-a jar

-some thin aluminum foil or mylar (the shiny stuff balloons and candy wrappers are made from)

-cardboard

-a nail

-tape

-a balloon or comb.

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from Kitchen Science Lab for Kids (Quarry Books 2014)

  1. Cut the cardboard to fit over the mouth of the jar, poke the nail through the cardboard, tape on two long, thin strips of foil or mylar (see photo) and place the whole thing in the jar so the foil strips hang down, touching each other.

 

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Electroscope from Kitchen Science Lab for Kids (Quarry Books 2014)

 

2. Charge your balloon or comb by rubbing it on your hair or clothing to give it a negative charge.  Bring the charged object close to the nail head.  You don’t      even have to touch it!

From Kitchen Science Lab for Kids (Quarry Books 2014)

From Kitchen Science Lab for Kids (Quarry Books 2014)

 

What happened? Some negatively-charged electrons jump from the comb to the nail and into the strips of foil.  The negative charge on the comb will push electrons (which are also negatively charged) down to the foil/mylar and give both strips a negative charge. The two strips try to move away from one another as the like charges repelled each other.

What happens when you make the strips out of different materials like paper?  Are there other charged objects you can use to make your foil strips “dance”?

You can also bend a thin stream of water from the faucet by holding your charged comb next to it.  The water is uncharged and is pulled toward the negative charge of the comb.

Try making small pieces of tissue paper float or dance by holding a charged comb or balloon next to them!  We filled an empty soda bottle with tiny pieces of foil and made them jump around with a charged comb held close to the bottle.

 

8 Spring Science Eggsperiments

 - by KitchenPantryScientist

Spring is egg season. You may prefer dyed eggs, hard-boiled eggs, deviled eggs, or even dinosaur eggs. No matter what kind of eggs you like best, you’ll love these eggsperiments that let you play with the amazing architecture of eggs, dissolve their shells and even dye them with the pigments found in your refrigerator. Just click on experiments for directions and the science behind the fun!

Grow alum crystals in eggshells to create beautiful geode-like works of art. 

Egg Geode from Kitchen Science Lab for Kids (Quarry Books)

Egg Geode from Kitchen Science Lab for Kids (Quarry Books)

Dye eggs with spices, fruits and vegetables,

or dye them with red cabbage juice and use lemon juice and baking soda to paint them.

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Dissolve eggshells with vinegar and play with osmosis when you make “Alien Monster Eggs.”

Alien Monster Eggs from Kitchen Science Lab for Kids (Quarry Books)

Alien Monster Eggs from Kitchen Science Lab for Kids (Quarry Books)

 

You can stand on a carton of eggs to test their strength.

Standing on Eggs from Kitchen Science Lab for Kids (Quarry Books 2015)

Standing on Eggs from Kitchen Science Lab for Kids (Quarry Books 2015)

For a fun physics experiment, throw eggs at a hanging sheet.

From "Kitchen Science Lab for Kids" Quarry Books

From “Kitchen Science Lab for Kids” Quarry Books

Make egg-eating monsters and watch atmospheric pressure push eggs up into a bottle.CZ1A9811p

Egg drops are a fun way to test your engineering prowess. 

And finally, here’s a little more about the science of hard-boiled eggs.

 

 

Soapy Science: Giant Bubbles

 - by KitchenPantryScientist

From surface tension to evaporation, science come into play every time you blow a bubble.

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Water molecules like to stick to each other , and scientists call this sticky, elastic tendency  “surface tension.” Soap molecules, have a hydrophobic (water-hating) end and (hydrophilic) a water-loving end and can lower the surface tension of water. When you blow a bubble, you create a thin film of water molecules sandwiched between two layers of soap  molecules, with their water-loving ends pointing toward the water, and their water-hating ends pointing out into the air.

As you might guess, the air pressure inside the elastic soapy sandwich layers of a bubble is slightly higher than the air pressure outside the bubble. Bubbles strive to be round, since the forces of surface tension rearrange their molecular structure to make them have the least amount of surface area possible, and of all three dimensional shapes, a sphere has the lowest surface area. Other forces, like your moving breath or a breeze can affect the shape of bubbles as well.

The thickness of the water/soap molecule is always changing slightly as the water layer evaporates, and light is hitting the soap layers from many angles, causing light waves to bounce around and interfere with each other, giving the bubble a multitude of colors.

Try making these giant bubbles at home this summer! They’re a blast! (It works best a day when it’s not too windy, and bubbles love humid days!)

To make your own giant bubble wand, you’ll need:

-Around 54 inches of cotton kitchen twine

-two sticks 1-3 feet long

-a metal washer

1. Tie string to the end of one stick.

2. Put a washer on the string and tie it to the end of the other stick so the washer is hanging in-between on around 36 inches of string. (See photo.) Tie remaining 18 inches of string to the end of the first stick. See photo!

This bubble wand is a little longer than 18 inches on a side.

This bubble wand is a little longer than 18 inches on a side.

For the bubbles:

-6 cups distilled or purified water

-1/2 cup cornstarch

-1 Tbs. baking powder

-1 Tbs. glycerine (Optional. Available at most pharmacies.)

-1/2 cup blue Dawn. The type of detergent can literally make or break your giant bubbles. Dawn Ultra (not concentrated) or Dawn Pro  are highly recommended. We used Dawn Ultra, which is available at Target.

1. Mix water and cornstarch. Add remaining ingredients and mix well without whipping up tiny bubbles. Use immediately, or stir again and use after an hour or so.

2. With the two sticks parallel and together, dip bubble wand into mixture, immersing all the string completely.

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3. Pull the string up out of the bubble mix and pull them apart slowly so that you form a string triangle with bubble in the middle.

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4. Move the wands or  blow bubbles with your breath. You can “close” the bubbles by moving the sticks together to close the gap between strings.

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What else could you try?

-Make another wand with longer or shorter string. How does it affect your bubbles?

-Try different recipes to see if you can improve the bubbles. Do other dish soaps work as well?

-Can you add scent to the bubbles, like vanilla or peppermint, or will it interfere with the surface tension?

-Can you figure out how to make a bubble inside another bubble?

 

 

 

 

Fossil Hunting

 - by KitchenPantryScientist

Every fossil has a story to tell.

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Whether it’s the spectacular specimen of a dinosaur curled up on it’s eggs or a tiny Crinoid ring, mineralized remains offer us a snapshot of the past, telling us not only what creatures lived where, but about how they lived and the world they inhabited.

Growing up surrounded by the flat-topped, windswept Flint Hills of Kansas, it was hard to imagine that I was living in the bottom of an ancient seabed, but there was evidence of the Permian period all around.

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Now, when my kids and I return to my hometown, a fossil-hunting trip is always part of our routine, and we hunt for shells and coral where roads cut through crumbling limestone and and chert (flint.) Looking up at layer after layer of rock and shells, I can almost feel the weight of the water that once covered the land.

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An episode of RadioLab we heard on the drive North from Kansas to Minnesota explained that coral keeps time and that by comparing modern coral to ancient  coral fossils, scientists discovered that millions of years ago, years were about 40 days shorter than they are now. Can you guess why? Give the podcast a listen here. My mind was blown!

A visit to the Flint Hills Discovery Center in Manhattan, KS gave us more insight into the amazing geology, ecology and anthropology of the Flint Hills and the Konza Prairie that blankets them. Most people don’t know that the great tallgrass prairies of the United States wouldn’t exist if not for humans, who have been burning them for thousands of years.

What do you know about where you live? What’s it like now? What do you think it was like long, long ago? Are there fossils nearby?

Here are some fossil-hunting resources I found online, in case you want to go exploring:

http://geology.about.com/od/fossilbasics/tp/parks-that-allow-fossil-collecting.htm

http://mentalfloss.com/article/50997/10-states-fossil-hunting-sites-public

http://www.fossilsites.com/

http://www.fossilguy.com/sites/

http://www.fossils-facts-and-finds.com/fossil_hunting_usa.html

 

Physics! Biology! Chemistry! Yeah!

 - by KitchenPantryScientist

I got together with some friends this weekend to do a quick iPhone recording of a chemistry song (on my Kitchen Pantry Scientist YouTube channel soon) and these awesome kids were nice enough take a break from playing to sing the Science Song with me. They had me laughing so hard that I could hardly get the words out!

Can you make up a song about science?