Home Scientist

By paying careful attention during experiments, scientists learn new things – even if they’ve done the test before. That means you don’t have to grow up to be a scientist. You’re a scientist every time you do an experiment! In this badge, find out where science has been hiding in your home.

Steps

Be a kitchen chemist
Create static electricity
Dive into density
Make something bubble up
Play with science

Purpose

When I’ve earned this badge, I’ll be able to see the science all around me.

Every step has three choices. Do ONE choice to complete each step. Inspired? Do more!

Tips Before Takeoff

Have an adult help you with ever single experiment. It’s also best to wear some old clothes – science can get messy!

Step 1 Be a kitchen chemist

Start your experimenting in the coolest place for science in your house – the kitchen! Science is responsible for making lots of different food. Try one of these experiments, then enjoy the food when you’re done!

CHOICES – DO ONE:

Make a salad dressing. Salad dressing is science in action! A Vinaigrette is made with two liquids that don’t want to blend. They need the help of an “emulsifier” to come together. Here, use mustard as your emulsifier to get vinegar and oil to mix into something yummy for your salad.
You’ll need:
1 teaspoon mustard
1 tablespoon vinegar
½ cup olive oil
Salt and pepper
Medium-size bowl
Whisk
Instructions: Put the mustard in the bowl. Add the vinegar and whisk, whisk, whisk! Slowly add the oil while continuing to whisk. Watch closely as the dressing gets smooth.
What happens? Look really close – your dressing is not a mixture (like vinegar and water would be), but actually tiny oil bubbles floating in vinegar, with the help of mustard. It’s an emulsion!
OR
Grow rock candy. Make your own candy from sugar crystals.
You’ll need:
1 cup water
4 cups sugar
Food coloring
Jar
Wooden skewers or string
Instructions: With an adult’s help, boil the water. Slowly pour in the sugar, letting it dissolve as you pour. When the sugar won’t dissolve anymore and begins building up on the bottom of the pan add a few drops of food coloring. (You can also add fruit flavoring now.) Pour this liquid into the jar, but don’t let any undissolved sugar get into the jar. Put skewers into the solution or tie string to a pencil and place the pencil across the jar.
What happens? Crystals should start to form after about an hour, but if you wait several days or weeks, your rock candy will form large crystals. Sugar is actually made of tiny crystals that clump together. The same idea is used to make rock candy.
FOR MORE FUN: Use a hand lens or magnifying glass to look really closely at how the crystals grow. Do they look different than salt crystals?
OR
Make your own ice cream. With the help of salt, ice cream stays creamy instead of turning into a block of ice.
You’ll need:
1 tablespoon sugar
½ cup whipping cream or half & half
¼ teaspoon vanilla
6 tablespoons rock salt or kosher salt
1 pint-size ziplock bag
1 gallon-size ziplock bag
Ice
Instructions: Fill the pint-size bag with sugar, milk, and vanilla, then seal it. Fill the gallon-size bag halfway with ice then add the salt. Place the pint bag inside the gallon bag and seal. Shake the bags for about 10 minutes, until you see ice cream forming in the small bag. (Wear gloves – your hands will get COLD.)
Tip: Double-bag both bags in case something leaks.
What happens? Salt helps keep the ice cream temperature low enough to freeze milk, and sugar helps keep the ice cream from freezing solid! (There’s more cool science in ice cream – with an adult find out more online.)

Step 2 Create static electricity

Ever wonder why your clothes sometimes cling to you? Or why you feel a shock when you touch a doorknob? It’s because of static electricity. Try one of these experiments to find out more about how it works.

CHOICES – DO ONE:

Follow the balloon leader. A balloon charged with static electricity can make a lot of different things follow it around the room!
You’ll need:
A balloon
A Ping-Pong ball
Paper
Bubbles (optional)
Instructions: Blow up the balloon and tie the end. Rub it on your hair. Then hold it close to a Ping-Pong ball. When you move the balloon, watch the science magic.
What happens? When you rub the balloon against your hair, you give it a negative charge. The balloon takes some of the electrons from your hair, which leaves your hair positively charged.
Your positively charged hair is now attracted to the negatively charged balloon, so your hair starts to rise up to meet it. This is similar to the Ping-Pong ball, which is drawn to the negatively charged balloon as the area near it becomes positively charged – opposite charges attract.
You also see how some charges repel here – after you rub the balloon, the strands of your hair repel each other!
FOR MORE FUN: Try the experiment again with small bits of paper or blow some bubbles and see if they’ll follow the balloon.
OR
Make pepper dance. See what happens when electric charges jump back and forth.
You’ll need:
Salt
Pepper
A sheet of paper
A balloon
Instructions: Pour some salt and pepper on the sheet of paper. Blow up the balloon and tie it. Rub it on your hair. Hold it over the salt and pepper and watch it “dance!”
What happens? After you rub the balloon on your hair, it gets a negative charge. When you bring it close to the salt and pepper, the charge attracts the pepper first because it’s lighter than salt. The pepper moves to the balloon where it gets a negative charge, which repels it back to the paper. There, it loses the charge, and the “dance” starts again.
OR
Bend water. See if you can bend water with static electricity.
You’ll need:
Running water from a tap
A plastic comb
A wool sweater
Instructions: Turn the water on in a very thin stream. Rub the comb very quickly on the sweater. Then bring the teeth of the comb near the water, about 3 – 4 inches below the facet. Watch closely!
What happens? The water bends toward the comb! By rubbing the comb against the sweater, you gave it a positive charge. This caused the water to be attracted to the charged item.
FOR MORE FUN: Try moving the comb different distances from the water. Then try running it through your hair more times. You could also try different kinds of combs.

Step 3 Dive into density

How come some things float, while others don’t? It’s all about density. Density is not weight but it’s related. For example, if you swim in the pool with blow-up floaties or a raft, you won’t sink because the air inside the floaties is less dense than the water around you. So the air helps hold you up! Try one of these to find out more about density.

CHOICES – DO ONE:

Egg in salt water. See if you can keep an egg suspended in the middle of a glass with this experiment.
You’ll need:
A tall glass or clear pitcher
4 tablespoons salt
2 cups water
Food coloring
An egg
Instructions: Mix the salt and one cup of water in the glass. Then add a few drops of food coloring. Mix to dissolve the salt. Slowly pour the remaining cup of plain water down the side of the glass. Carefully lower your egg into the glass.
What happens? The egg should sink until it hits the layer of salt water. (The food coloring is to help you see the boundary between the salt water and plain water.) Why does the egg stop sinking? Because the salt water is denser than the egg.
OR
Dancing raisins. Can you make raisins move without touching them? Try this experiment.
You’ll need:
Can of clear soda
Tall glass
A small box of raisins
Instructions: Pour the soda into the glass. Drop 6 or 7 raisins into the soda. Watch them for a few seconds.
What happens? Raisins are denser than the soda so at first they sink. But then the bubbles from the soda fill the wrinkles in the raisins, lifting them up. When the bubbles reach the top of the glass, they pop, and the raisins sink again.
OR
Lemons vs. limes. Lemons and limes seem very alike. But are they really?
You’ll need:
A deep container
A lemon
A lime
Instructions: Fill a deep container (see-through, if possible) with water. Add the lemon and lime.
What happens? Usually the lemon will float and the lime won’t. This is because a lime is denser than water, but a lemon is not.
FOR MORE FUN: Try the experiment again with different juicy fruits. You could use an orange with peel and one without, and then add more fruits with and without peels. Which float and which sink? Are any of them in the middle?
Try a diet soda and a regular soda of the same brand. What makes the difference?

Step 4 Make something bubble up

When mixed with a gas called carbon dioxide, some household items can have a fun reaction. Check out how carbon dioxide reacts with different elements.

IMPORTANT TIP: Make sure you wear sunglasses or safety glasses for these experiments!

CHOICES – DO ONE:

Soda geyser. A geyser is a hole in the earth that sprays out hot water and steam. So making your own is definitely and outside experiment!
You’ll need:
2-liter bottle of Coke (Diet or Regular but Diet can kill grass)
Roll of Mentos candy (mint works best)
Long piece of scotch tape
Instructions: Take the top off the soda bottle and set the bottle on the ground somewhere outside with nothing else around. Open the package of Mentos candy, and stick them along a piece of tape so you can drop them all into the soda at once. When you are ready to make the drop, be ready to run and stand back!
What happens? A soda geyser will erupt because of the carbon dioxide gas created by the rapid reaction between the candy and soda.
OR
Film-canister rockets. If a gas like carbon dioxide builds up, it can create a strong force.
You’ll need:
An old, white 35mm film canister with a pop-in lid (not pop-on) available at photo stores
Water Alka Seltzer tablets
Instructions: Fill the film canister half-full with water. Cut the Alka Seltzer tablet into 4 pieces and drop the pieces into the canister. Snap on the lid – quickly. Time the reaction!
What happens? The carbon dioxide created by the reaction in the canister should pop the top off the canister.
FOR MORE FUN: Make Try again changing the amount of water or Alka Seltzer. Is there a best combination?
OR
Blow up a balloon without using your breath. Gases like carbon dioxide will try to find a place to go when they are expanding in confined spaces. Test this out by showing your friends how to blow up a balloon without using your breath. Be careful – the balloon might pop!
You’ll need:
2 spoons
2 tablespoons vinegar
A clean empty plastic bottle
A balloon
1 teaspoon baking soda
Instructions: With one of the spoons, add the vinegar to the bottle. Ask a friend or an adult to hold open the mouth of the balloon and, using the other spoon, pour baking soda into the balloon. Then stretch the balloon’s opening over the mouth of the bottle. Make sure the baking soda inside the balloon falls into the vinegar.
What happens? The baking soda and vinegar create carbon dioxide when they mix. There is not enough room inside the bottle for the extra gas, so it expands into the balloon, blowing it up!

Step 5 Play with science

Science can also be used to make things that are just plain fun. Use science to make one of these homemade “toys” and amaze your friends!

CHOICES – DO ONE:

Giant bubbles. These are even more fun than the small ones with the standard bubble wand.
You’ll need:
Cotton string
A large plastic tub
2 plastic straws
1 cup dishwashing soap
4 cups water
½ cup light-colored corn syrup or glyceri
Instructions: To make your bubble blower, cut a long piece of string and thread it through two straws. Tie the ends of the string together, and then slide the knot into the middle of one of the straws. You can adjust the blower size by making the length of string shorter or longer before tying ends. Pour the liquids into the tub and mix. Dip your blower into the tub. Holding the straws, slowly spin around. With some practice, you should create huge bubbles!
OR
Homemade Silly Putty. Silly Putty is fun goo that you can stretch, stamp, and play with. Instead of buying some, why not make your own?
You’ll need:
Food coloring
¾ cup glue
¼ cup liquid starch or borax
Mixing bowl
Water
Instructions: In the bowl, mix 8 drops of food coloring in the glue, and 1 cup of water. Mix the borax with 1 1/3 cups water. Slowly add the liquid starch or borax mixture to the colored glue and water mixture. Knead the mixture until you can stretch it but it isn’t too mushy. Store in a plastic bag or covered container. (If it’s out in the air for more than two hours it will harden!)
OR
Make dinosaur snot. Okay, so maybe it isn’t real . . . but it sure looks like it!
You’ll need:
A mixing bowl
1½ cups cornstarch
1 cup water
Yellow and green food coloring
Instructions: In the bowl, mix the cornstarch and water. Add a few drops of yellow and green food coloring to the mixture. Use your hands to make sure it is really combined. After about a minute, you’ll have stretchy slime that looks like it came from a dinosaur. Achoo!

Add the Badge to Your Journey

Now that you are having fun with the science all around you, how about adding a little fun with haiku. Check out the examples on page 28 in your Brownie Quest and make up a haiku to go with one of the science experiments in this badge!

Now that I’ve earned this badge, I can give service by:

Helping Daisies make giant bubbles
Sharing the science of ice cream with my friends
Making a healthy salad for my family and explaining the science behind the dressing

Other Badges