Category:Chemistry Experiments’

Ice Science: Lifting an Ice Cube Using Salt and a String

 - by KitchenPantryScientist

Have you ever wondered why putting chemicals like salt on a road makes the ice melt?

To see how NaCl (table salt) melts ice by lowers the melting temperature of water, you’ll need an ice cube, a glass of water, and a piece of kitchen twine or string about 6 inches long and salt.

What to do:

Drop an ice cube in a glass of ice water.  Try to pick the ice cube up without your fingers by simply placing the string on it and pulling up.  Impossible, right?

From Kitchen Science Lab for Kids (Quarry Books 2014)

From Kitchen Science Lab for Kids (Quarry Books 2014)

 

Now, dip the string in water, lay it across the ice cube and sprinkle a generous amount of salt over the string/ice cube.  Wait about a minute and try again to lift the cube using only the string.  What happens?

From Kitchen Science Lab for Kids (Quarry Books 2014)

From Kitchen Science Lab for Kids (Quarry Books 2014)

 

It may seem like magic, but it’s only science. Here’s a video from my KidScience app where I demonstrate the experiment.

Salt lowers the temperature at which ice can melt and water can freeze.  Usually, ice melts and water freezes at 32 degrees Farenheit, but if you add salt to it, ice will melt at a lower (colder) temperature.

The salt helps the ice surrounding the string start to melt, and it takes heat from the surrounding water, which then re-freezes around the string.

Different chemicals change the freezing point of water differently.  Salt can thaw ice at 15 degrees F, but at 0 degrees F, it won’t do anything.  Other de-icing chemicals they add to roads can work at much colder temperatures (down to 20 degrees below zero.)  If it’s cold enough, even chemicals won’t melt the ice.

Brrr.

Pressure can also make ice melt at colder temperatures.  This is why ice skates glide on rinks.  The pressure is constantly melting the ice a where the blade presses down on it so the blade glides on a thin layer of water!

Give the Gift of #STEM: Homemade Science Kit

 - by KitchenPantryScientist

Image from “Kitchen Science Lab for Kids” (Quarry Books 2014)

There are few gifts more fun than a homemade science kit. Give a kid a bottle of vinegar and a box of baking soda and you’ll make their day. Throw in a bottle of Diet Coke and some Mentos mints, and you may be their favorite person ever. Make a kit for your kids or grand kids. Make one for your favorite niece or nephew. Encourage kids to make kits for friends and siblings.

Here are some ideas for items to include in your kit.I’ve highlighted links to the experiments on my website (just click on the blue experiment name) in case you want to print out directions to add to your kit. You can also find these experiments on my Kitchen Pantry Scientist YouTube channel!

-composition book: Makes a great science notebook to draw, record, and tape photos of experiments into.
-clear plastic cups to use as test tubes and beakers
-measuring spoons and cups 
-school glue (white or clear) for making Mad Scientist’s Slime
-contact lens solution for making Borax-free Slime
-gummy worms to transform into Frankenworms
-baking soda: Can be used for a number of experiments like fizzy balloons, magic potion . Or just mix with vinegar to make carbon dioxide bubbles.
-vinegar Great for fizzy balloons , alien monster eggs and magic potion.
-balloons for fizzy balloons.
-dry yeast for yeast balloons.
-white coffee filters: can be used for magic marker chromatography, in place of a paper bag for a coffee-filter volcano or making red cabbage litmus paper.
-cornstarch:Lets you play with Cornstarch Goo, a non-newtonian fluid. Here’s the video.
-marshmallows with rubber bands and prescription bottle rings you have around the house can be used to make marshmallow catapults. My kids used theirs to make their own Angry Birds game.
-Knox gelatin and beef bouillon cubes can be used to make petri plates for culturing microbes from around the house. You can also use the gelatin for cool osmosis experiments!
-food coloring Helps you learn about surface tension by making Tie Dye Milk. Here’s the video. You can also easily make colorful sugar-water gradients that illustrate liquid density!
-Mentos mints will make a Mentos geyser when combined with a 2L bottle of Diet Coke.
-drinking straws are great for NASA soda straw rockets and a carbon dioxide experiment.

To take it up a notch, throw in a copy of one of my book! You can find them on Amazon, Barnes and Noble and anywhere else books are sold! 

Happy Experimenting! 

 

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!

14 Freaky Halloween Science Projects for Kids

 - by KitchenPantryScientist

Turn your kitchen table into the coolest mad science lab in the neighborhood. Click on the project name for link to written how-to instructions and the science behind the fun!

1. Frankenworms– Bring gummy worms to “life” using baking soda and vinegar.

2. Alien Monster Eggs– Make creepy, squishy monster eggs.

3. Oozing Monster Heads– Combine science and art to create Halloween fun.

4. Bag of Blood– Amaze your friends with this magical science trick.

5. Vampire Rock Candy

Vampire Rock Candy (kitchenpantryscientist.com)

 

 

 

 

 

 

 

 

 

 

 

6. Cornstarch Goo

7. Jell-O Eyeballs

Jell-O Eyeballs
kitchenpantryscientist.com

 

 

 

 

 

 

 

 

 

 

 

 

8. Vegetable Vampires

Vegetable Vampires kitchenpantryscientist.com

 

 

 

 

 

 

 

 

 

 

 

 

9. Magic Potion– Make a color-changing, foaming potion using red cabbage and water.

10. Halloween Soda Explosion– Halloweenize the classic Diet Coke and Mentos explosion

11. Foaming Alien Blood– Bring the X-Files to your kitchen with this creepy green fake blood

12. Mad Scientist’s Green Slime– Because everyone loves slime

13. Homemade Fake Blood– It’s simple to make non-toxic fake blood in your kitchen.

14. Fizzy Balloons– Draw scary faces on balloons and blow them up using baking soda and vinegar.

Elemental Science: Gallium

 - by KitchenPantryScientist

Gallium is a soft metal related to other metals in Group 13 of the periodic table, including aluminum. It doesn’t exist as a free element in nature, but can be purified from other metallic ores, like zinc. Each gallium atom has 31 protons in its nucleus, so its atomic number is 31.

You’ll find it around you in thermometers, semiconductors, and even some LED lights, and one property that makes it so cool is that it melts from solid to liquid at low temperatures (around 85.6 degrees F or 29.8 degrees C.) This makes it easy to play with the liquid metal simply by melting it in a glass of hot water, or in the palm of your hand.

You can see the crystal structure in the side of the gallium “Lego” we created in play dough! KitchenPantryScientist.com

*Not for small children! Wearing gloves and safety goggles is recommended when observing gallium. Although is is fairly safe, gallium will coat hands with a lead-like substance. (Wash with soap and water to remove.) Gallium can also damage other metals, so keep it away from jewelry, like rings. I always recommend doing your research, as well as checking out the MSDS (Material Data Safety Sheet) of a new substance before using it to know what precautions to take.

We ordered 99.99% pure gallium on Amazon. It arrived in plastic tubes,in crystal form, but by placing the tubes in hot tap water, it melted easily. Eye droppers work well for moving the melted metal around. I’d recommend using a rimmed paper plate to contain the mess.

Try imprinting a Lego or toy car in play dough and pouring the molten gallium into the imprint. When it solidifies, you’ll have a cast of the item you imprinted! (It takes a while.) Gallium coats glass to create mirrored surfaces, so you can pour some into a small jar and use it to coat the sides. If you leave some in a puddle on the bottom of an upside-down jar, you can watch crystals form.

In other words, it’s pretty awesome!

Kid-Friendly “Elephant Toothpaste”

 - by KitchenPantryScientist

I’ve been hearing about this science demonstration for years, and finally decided to try it! If you do it at home, kids should wear safety goggles or sunglasses to protect their eyes, and adults should pour the 3% hydrogen peroxide into the bottles.

You’ll need:
a tray or cookie sheet
3% hydrogen peroxide (available at most pharmacies and discount stores)
liquid dish soap
dry yeast (2 packets)
food coloring
empty 16 oz bottle

What to do:
1. Pour 1 cup hydrogen peroxide into an empty 16oz bottle. (A funnel helps!)
2. Add 2 Tbs. liquid dish soap to the bottle and mix well with the hydrogen peroxide.
3. Put 8 drops of food coloring into the bottle and swirl to mix.
4. Position the bottle on the tray.
5. Pour 2 packets of yeast into a paper cup and pinch the cup’s lip to make a pouring spout.
6. Quickly pour the yeast into the bottle, while swirling the liquid vigorously to mix well. The better you mix it, the better the experiment will work!
7. Set the bottle down on the tray before the foam emerges from the top.
8. Watch the chemical reaction between catalase in the yeast and the hydrogen peroxide create oxygen bubbles in the soap!
9. When the reactions has stopped, have an adult clean up the mess by pouring everything down the sink and rinsing the tray with water. (Normally kids should clean up, but for this one, I’d recommend an adult do it.)

The Science Behind the Fun:

Hydrogen Peroxide (H2O2) is a common household chemical that is often used to disinfect wounds and bleach hair. Certain chemicals can break it down into water (H2O) and Oxygen (O).

Dry yeast is a living fungus that produces a molecule called catalase. Catalase is very good at breaking down hydrogen peroxide quickly. When you add yeast to hydrogen peroxide that’s been mixed with liquid soap, the soap traps the oxygen and makes bubbles that push their way out of the bottle.

You may notice that the bottle feels warm. That’s because the chemical reaction produces heat and is called an exothermic reaction.

Homemade Tie-Dye Fidget Spinner

 - by KitchenPantryScientist

Homemade Spinner with Tie-Dye Edges (KitchenPantryScientist.com)

Make a super-cool spinning toy using skateboard bearings, super glue and a little physics. Customize your design with a marker tie-dyed shoelace.

Warning: Not for recommended for kids under 5. Use adult supervision for super glue, sharp points, rubbing alcohol and glue gun.

You’ll need:

-4 skateboard bearings (available online or at skateboard stores)
-superglue or Krazy Glue
-a white shoelace
-permanent markers, like Sharpies
-rubbing alcohol (isopropanol)
-a glue gun

KitchenPantryScientist.com

1. Use a sharp point to remove the cover from one of the bearings so that you can see the ball bearings inside. (See image above.)
2. Cut a piece of paper 6cm x 6cm and draw an X from corner to corner.
3. Center the bearing with the cover removed in the middle of the X. Then, center the other 3 bearings around the one in the middle so that they’re evenly spaced. You can use a ruler to check spacing. (See image below.)

KitchenPantryScientist.com

4. Add a single drop of super glue to the junction between each bearing to connect them. If you add too much, the spinner will stick to the paper. *Be careful not to get any glue onto the moving parts of the bearings.

KitchenPantryScientist.com

5. When the glue is dry, carefully turn the spinner over and place another drop of glue at each junction.

6. When the glue is dry, prop the spinner up on its side and add glue to the junctions on the sides. (See image below.) Repeat on each side.

KitchenPantryScientist.com

7. While the spinner glue is drying, make dots of permanent marker on the shoelace. In a well-ventilated area, suspend the shoelace over a tray or colander and drip rubbing alcohol onto it to make the colors run together. (See image.) Let it dry completely.

KitchenPantryScientist.com

8. Use the glue gun to attach the shoelace to the outside edges of the spinner. Fill in gaps between the lace and bearings with hot glue.

KitchenPantryScientist.com

9. Spin away!

The Science Behind the Fun:

If you look closely at a skateboard bearing there are only a few ball bearings connecting the center and the outside part that spins. This means that there’s very little friction, or rubbing, between the parts. If you spin the toy around the center bearing, that bearing is called the axis of rotation.

The three bearings on the outside of the spinner provide the rotating mass that gives the toy a property called angular momentum, which keeps it spinning until the frictional force from the ball bearings in the center slows it down.

Pigments are molecules that give things color. The pigments in permanent markers are trapped in ink compounds that are insoluable in water, which means that they won’t dissolve in water. However, if you add a solvent, like rubbing alcohol, or isopropanol, to permanent markers, it dissolves the ink. As the alcohol moves through the cloth you are decorating, it carries the pigments along with it.

Earth Day Science

 - by KitchenPantryScientist

Saturday April 22nd is Earth Day, so get outside and show our home planet some love! Whether you’re picking up trash or visiting a park, it’s always fun to throw some science into the mix.

Here are some of our favorite environmental science experiments. Just click on the experiment names for directions and photos. You can find more fun outdoor experiments in my books “Kitchen Science Lab for Kids” and Outdoor Science Lab for Kids (Quarry Books.)

from "Outdoor Science Lab for Kids" (Quarry Books)

from “Outdoor Science Lab for Kids” (Quarry Books)

Homemade Sweep Nets: Make a sweep net from a pillowcase and a hanger to see what arthropods are hanging out in your favorite outdoor spaces.

Window Sprouts: Plant a bean in a plastic baggie with a damp paper towel to see how plants need only water and air to sprout roots and leaves.  Here’s a short video demonstrating how to make a window garden.

Homemade Solar Oven: Using a pizza box, aluminum foil, plastic wrap, and newspaper, you can harness the sun’s energy to cook your own S’mores!

Nature Walk Bracelets: Wrap some duct tape around your wrist (inside out) and take a walk, sticking interesting natural objects like leaves and flowers to your bracelet. It’s a great way to get outdoors and engage with nature!

Carbon Dioxide and Ocean Acidity: See for yourself how the carbon dioxide in your own breath can make a water-based solution more acidic. It’s the same reason too much carbon dioxide in Earth’s atmosphere can be bad for our oceans.

9781631591150

Plant Transpiration:  See how trees “sweat” in this survival science experiment.

Earthworm Experiment:  Do you know what kind of earthworms are living in your back yard?

Composting: Be a composting detective. Bury some things in your back yard (away from power cables) and dig them up in a few months to see how they look. Composting reduces methane gas emissions (a greenhouse gas) from dumps.

Diffusion and Osmosis: See for yourself how the chemicals we add to water, put on our streets to melt ice, and spray on our lawns and crops can move into our soil, ground water, rivers, lakes and oceans.

Solar Water Purification: This project illustrates the greenhouse effect and is a fun “survival science” experiment. Requires hot sun and some patience!

Citizen Science: Don’t forget about all the real environmental research projects you can participate in through Citizen Science programs all around the world!

For mores activities and games, check out NASA’s Climate Kids website, to see a kid-friendly diagram of the water cycle, click here or just get outside and enjoy the beautiful planet that sustains and nurtures us.

Nail Polish Marbled Eggs

 - by KitchenPantryScientist

Nail polish marbling is tons of fun and yields stunning results. However, it takes some eye-hand coordination, practice and patience, so I’d recommend it for ages 10 and up. My 11 YO loved it!

KitchenPantryScientist.com

KitchenPantryScientist.com

Hint: You’ll have to work reasonably fast for good results. Gloves are a must, and do this in a well-ventilated area to avoid breathing too many nail polish fumes.

You’ll need:

-eggs with the raw yolks and whites blown out (We poked generous holes in each end of our eggs using a thumb tack, scrambled the inside with a toothpick and used syringes and balloon pumps to blow out the raw whites and yolks. It takes patience, and you’ll lose a few eggs to cracks.)

-a container that can be thrown away

-nail polish in two or more colors

-a toothpick

-water

1. Fill your container 3/4 full of water.
2. Drip nail polish, a drop at a time into the center of the water. Each drop should be in the center of the one before. Don’t worry if they spread out, just keep adding more. You’ll have to work fast, or the polish will dry on top of the water. It may take practice.

Kitchen Pantry Scientist.com

Kitchen Pantry Scientist.com

3. Use tip of the toothpick to draw designs in the polish. Start by pulling it out from the center or pushing it into the center.

KitchenPantryScientist.com

KitchenPantryScientist.com

KitchenPantryScientist.com

KitchenPantryScientist.com

4. When the design is ready, roll it onto your egg like you’re rolling a bandage around an ankle. Try to keep in smooth and in a single layer. If it looks bad, try another one. You’ll get the hang of it!

KitchenPantryScientist.com

KitchenPantryScientist.com

5. Put the marbled egg on an egg carton to dry.

The science behind the fun: Nail polish is less dense than water and floats on top of it. It contains a solvent called acetate that evaporates very quickly into the air, drying out the polish.