Every year, KAST branches out, bringing only the best science experiments to summer camps all over the Kootenay area. This booklet contains some of the favorite experiments that we have shared with kids across the region. They are here for you to experiment with, get messy with, show to friends, and learn from. We hope that we can share the fun and fascinating nature of science with you not only during the summer, but for the whole year round. 1
Materials -
One boiled egg Glass bottle with a neck smaller than an egg Matches
Procedure 1. Peel the shell off of the boiled egg 2. Place the egg on top of the bottle. Leave it there for a while and notice that it won’t go down 3. Light two matches – quickly lift the egg and drop the matches into the bottle. Put the egg back on top. 4. After a few seconds, the matches will go out and the egg will squeeze down into the bottle 5. To get the egg back out, turn the bottle upside-down and blow hard into it for a few seconds. This will increase the air pressure and the egg will come back out
Explanation When the matches are dropped into the bottle, they hear the air up. The warm air expands and some of it flows outside of the bottle; when the matches go out, the air cools back down and the pressure inside the bottle drops. The air outside of the bottle has a higher pressure than inside and it pushes its way back in, forcing the egg to come with it.
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Materials -
Two identical forks 2 toothpicks Glass Salt shaker
Procedure 1. Link the prongs of the two forks together 2. Insert a toothpick through the prongs so that about 1 cm sticks out from the back. Balance the toothpick on the rim of the glass, halfway between the end of the toothpick and the forks. 3. Put the other toothpick into a hole on top of a salt shaker (make sure it fits snugly) 4. Take the toothpick from the glass and balance the tips of the two together
Human Center of Gravity - Bend forward and grab your toes. Try to jump forwards without letting go. - Sit in an armless chair with feet flat to the ground and against the back. Try to get up without lifting your feet or bending your back. - Place an object on the floor about 20 inches from a wall. Stand with your back against the wall, feet together, and heels against the wall. Try to pick up the object on the floor without moving your feet or bending your knees. - Stand against a wall with your right side facing the wall, and then put your right foot and cheek against the wall. Try to lift your left foot off the floor.
Explanation Every object has a center of gravity, around which the weight is evenly spread. You can balance things in a seemingly impossible way if you position their centers of gravity correctly. Hint - Look up on YouTube how to link the forks and place the toothpick in – it takes practice! 3
Materials -
Several sheets of construction paper A small book Masking tape A piece of corrugated cardboard (optional)
Procedure 1. First, see if you can balance a book on the upright edge of a flat sheet of construction paper. What happens? 2. Next try folding the paper into a V-shape and put the book on top. What happens now? 3. How about this: Roll the piece of construction paper along its short side, using adhesive or masking tape to keep it rolled into a cylinder shape. Now place the book on top of the tube. What happens this time? Is the paper tube strong enough to support the book? 4. Can you think of other ways to fold the construction paper so that it will support something as heavy as a book? Try different sizes of tubes, triangular shapes, accordion folds, and I-beam shapes.
Explanation The shape of the piece of paper affects its strength. A piece of paper is not very strong on its own, but when it is rolled into a cylinder or accordion shape, it becomes quite strong. This is because the weight being placed on it is distributed throughout the structure. The accordion shape forms ‘almost triangles’ which makes the paper much stronger. Companies that manufacture corrugated boxes use this principle to make the material that boxes are made of. If you look at the edge of a flap on a shipping box, you'll see that it consists of two flat sheets of brown paper with a layer of "wavy" paper sandwiched in between. Each "wave" is called a "flute," and the material is called "corrugated board." It's what makes boxes strong enough to carry lots of different products without being crushed.
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Materials -
Light construction paper or blank white paper Plastic cups for each color of paint Straws About 1/3 of each cup full of dish soap/color A bit of water for each color Lots of food coloring for each color
Procedure 1. Mix dish soap, water and food coloring to make the paint 2. Make several different colors with food coloring 3. Blow with straw into the solution until bubbles start to come over the top of the cup. If they’re not staying, just keep adding a bit more water 4. Gently press the paper on top of the bubbles and they will pop, leaving a ring of color
Explanation Bubbles are created when a thin film of soap and water is stretched and filled with air. The water alone can’t form a bubble but with soap, it can hold the shape because the soap stabilizes the surface. It also strengthens the weak areas and decreases the surface tension, which allows the bubble to hold its shape. For lots of bubbles to fit very closely together, they stack together as six-sided hexagons – a structure that requires the least energy possible. Hexagons easily stack together without any gaps in between, which makes the shapes strong and durable.
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Materials -
Balloons Hole punchings from paper
Procedure 1. Have the kids blow up the balloons and rub then gently on their hair. They’ll notice the hair standing up. Talk to them a bit about static electricity 2. Have the hole punchings on the floor and have them hold the balloon close to the papers without touching them 3. Have them transfer their hole punchings to another place on the floor via the balloon
Explanation When the balloons are rubbed on the hair, they pick up a few tiny electrons from the hair, giving them a small negative charge. The paper confetti has a small positive charge, so it is attracted to the balloon – just like magnet ends are attracted to each other. The attraction allows the paper punchings to be picked up and transferred.
Hint: Make this into a relay race – divide into teams and see which team can create the most static electricity and transfer their paper punchings first.
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Materials -
Bugs Jars Eyedropper Water Greenery for the bugs
Procedure 1. 2. 3. 4. 5. 6.
Set up a few jars with grass, leaves, and twigs for the bugs to be around Catch bugs and put them in jars with holes in the lids (so they can breathe) Put ears up to the jars and listen to what kind of noises the bugs are making Watch the bugs for a while to see what kind of things they do Drop some water onto the leaves or grass and see if they go to it Take bugs into a colder room or a warmer room (in the sunshine) to see how the temperature affects their activity 7. Let bugs go back where they were found
Hint – Make up a chart to fill in. What happens to the bugs when they are placed in different areas, how to they look, what they sound like, etc. Put a box at the end of each to draw a picture of what each bug looked like
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Materials -
Empty soda can Boiling water (kettle) Cold water (and ice) Balloon with the end cut off Elastic band Tongs Large bowl
Procedure 1. Fill the bowl with cold water and ice. The bigger the difference between the two temperatures, the better this will work 2. Add boiling water to the can so it is about 1/3 – 1/2 full 3. Quickly stretch the balloon over the top of the can and place the elastic around it 4. Grab the can with the tongs and place it upside down in the cold water
Explanation By boiling the water, the water changed states from a liquid to a gas (steam); the steam pushed the air that was originally in the can outside When the can was placed in the water, the steam cooled down and turned back in to water; water molecules are a lot closer together than gas molecules All of the steam that filled up the whole can turned back into only a few drops of liquid, which took up much less space. This small amount of liquid cannot exert much pressure on the inside of the can, so the water from the outside pushed in and crushed the can
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Materials -
Two glasses Food colouring White flower (carnation) with a long stem Tape Knife Cutting board Water
Procedure 1. Slice the stem (about halfway up) in half so it has two separate stems 2. Wrap some tape around the stem where the slice stops to prevent from splitting further 3. Fill the glasses with water and add food coloring to one of them (the more food coloring, the better the effect). Place the flower in the glasses, with half a stem in each 4. Check the petals and notice that half turn a color while the other half stay the same. This experiment can take a few days to completely turn.
Explanation Plants draw water up through their roots and into their stems. They do this by using xylem, which are hollow cells in the stem. The water goes up and into both the leaves and the petals so that the plant doesn’t wilt and is nourished. Since the stem is split in this one, half of the xylem get their water from the clear water and the other half from the colored water. When the water travels up, the dye stays with it and it colors the petals of half the flower.
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Materials: -
2 L bottle of Diet Coke (any other pop works as well, but diet pop makes the ground much less sticky afterwards) About 5 Mentos (*Only the regular work, not the colored ones with the candy coating)
Procedure: 1. Open the bottle of Diet Coke and sit it on level ground 2. Drop in the Mentos all together and run away immediately 3. Watch the fountain
Explanation: The Mentos are covered in tiny craters (like the moon) and the bubbles from the carbonation in the pop get inside of them and form carbon dioxide. Since the carbon dioxide is trapped inside the bottle, it has nowhere to go except up through the opening. It goes really fast which makes enough pressure to create a geyser. Hint – Will it work with the pop two times – most think that it will, but if you try it, it doesn’t. This is because all of the carbonation is gone after the first time. Put the lid on and shake it – there are hardly any bubbles at all Hint - Try with different types of pop to see which one makes the highest spray Hint - In order to drop the Mentos easier, make a tube that is just bigger than the Mentos out of paper; cover one end of the tube with a card and place it on the bottle (so they don’t fall in until the car is removed). When everyone is ready, remove the card and they’ll all fall in
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Materials -
Honey Corn syrup Maple syrup Milk Dish soap Vegetable oil Rubbing alcohol Water Tall glass or jar Various items to drop
Procedure 1. Measure color them with food coloring (apart from honey and vegetable oil) 2. Pour very slowly and be sure to not get any of the liquids on the sides of the container! 3. Pour in this order: Honey, corn syrup, maple syrup, milk, dish soap, water, vegetable oil, rubbing alcohol (use picture as reference) 4. After they are all in, drop the various objects in and see how far down they all fall (ex. bolt, cherry tomato, beads, Styrofoam, soda cap, marbles, cotton ball) Guess first!
Explanation The different liquids have varying densities, which makes them not sink through each other to the bottom or mix. They will sit like this as long as you leave them. Even if you shake them, most of them will go back to their original places.
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Materials -
One empty water bottle (no larger than 1L) One tray to do the experiment on (or cover table with plastic) 1 Styrofoam or plastic cup 1 plastic spoon Food coloring 1/3 cup water Gloves (for everyone who will touch it) ½ cup of 6% Hydrogen Peroxide 2 tablespoons of dish soap 1 tablespoon of Potassium Iodide
Procedure 1. 2. 3. 4. 5. 6. 7.
Put on gloves and place empty water bottle on tray or plastic cover (this will stain!) Carefully add Hydrogen Peroxide into the bottle Add about 6-8 drops of food coloring to the bottle Pour in the dish soap and swirl around until well mixed In the cup, add Potassium Iodide and water; mix until it’s all dissolved Carefully pour the Potassium Iodide solution in the bottle and swirl until bubbles appear Feel the heat that is being produced by this reaction
Explanation The foam is made of tiny bubbles, each filled with oxygen gas. The Potassium Iodide acts as a catalyst to remove the oxygen from the Hydrogen Peroxide. This creates a fast reaction that produces lots of tiny oxygen bubbles. The bottle becomes warm because the removal of oxygen from Hydrogen Peroxide gives off heat.
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Materials -
Two eggs Water At least 6 tablespoons coarse salt Two tall drinking glasses Food coloring
Procedure 1. Pour water into one of the glasses and then place the egg in it carefully. Notice how the egg sinks to the bottom right away. 2. Pour strong saltwater into the other glass and wait for it to settle. Gently lower the egg into the water and notice that it floats 3. Ask the kids whether they think drops of food coloring will sink or float. What will happen when they are stirred in – will they rise back to the top if they’re left for a few hours?
Explanation Salt water is denser than ordinary tap water, the denser the liquid the easier it is for an object to float in it. When you lower the egg into the liquid it drops through the normal tap water because it’s not dense enough to float on. The salt water is much denser, enabling the egg to amazingly float. In the Dead Sea, the salt concentration is about 30% so even people, waterproof books, and drinks can float. Hint – Explain density in terms of a net of molecules. The fresh water ‘net’ has lots of gaps in between so the egg can easily slip through to the bottom, whereas the salt water ‘net’ is woven tightly and allows the egg to sit on top of it.
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Materials -
4 Clear Containers Water Salt Water (very salty) Vinegar Baking Soda Gummy Bears
Procedure 1. Fill the four clear containers with water, salt water, vinegar, and baking soda water (one liquid per container) 2. Place a gummy bear in each of the containers. Guess what will happen to each (what happens to us when we sit in water for a long time?) 3. Leave overnight. Take the gummy bears out carefully the next day. *Must be in a cool place – gummy bears with melt and disappear otherwise
Explanation The gummy bears grew due to osmosis – the movement of water. Because the water concentration was lower inside the gummy bears, the water wanted to move into them. The baking soda cleaned the color out of the gummy bear. Baking soda is a cleaning agent. The vinegar ate away at the gelatin in the gummy bear, making it almost disappear.
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Materials -
Large glass jar Small glass Food coloring Knife Plastic wrap Rubber band Water
Procedure 1. Fill the large jar almost full with cold water from the tap and add ice if wanted (the bigger the difference in temperature, the better it works) 2. Fill the small cup or beaker with very hot (almost boiling) water and add several drops of ‘hot colored’ food coloring. Stretch the plastic wrap smoothly over the cup and seal it with the rubber band. (The plastic wrap will puff up because the hot air above the water is expanding). Gently place the hot jar into the cold jar and let it sink to the bottom. 3. Slice open the plastic wrap with the knife and watch what happens 4. What happens as the colored water gets to the top? Does it stay there? Why or why not?
Explanation The hot water was less dense than the cold water surrounding it, so it rose to the top. Have you ever heard that hot air rises? It's true! As air heats up, its molecules expand and spread out, making the air less dense than it was before. It floats up through the denser cooler air. As the warm air rises it starts to cool off and its molecules move closer together, causing it to sink again. Have you ever gone swimming and noticed the water at the top was nice and warm, but once you went in, it was freezing at the bottom? This is because of the densities. It’s also why fish stay deeper in the water during the day, because the top is too warm for their liking.
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Materials -
Water Food coloring Plastic containers of various sizes Plastic eyedroppers Salt, coarse salt, or rock salt
Procedure 1. Fill the containers with water and freeze overnight. Fill them up to different levels and try to get different sizes/shapes 2. Dump out the ice into a tray in the sunshine 3. Drop salt on the top surface of the ice and wait a little bit 4. Take the eye droppers and drop different colors on top of where the salt was 5. Continue steps 3 and 4 until they are satisfied 6. Hold the ice up towards the sun to see the tunnels formed by the salt and food coloring 7. Try with the different types of salt to see their different effects on the ice
Explanation Salt lowers the freezing point of water and therefore causes a little bit of the ice to melt with each grain. This creates the tunnels. The food coloring goes in the tunnels and follows the path that the salt carves out, making us able to see it. In the winter, we put salt on ice for the same reason – the ice melts a little bit so we don’t slip 16
Materials -
Bar of Ivory soap Paper towel or microwave-safe dish Microwave oven
Procedure 1. Place the soap onto the paper towel or dish 2. Put inside the microwave and heat for 2 minutes on high (can heat for longer but it will not grow any longer) 3. Allow the soap to cool off for at least 1 minute before touching it 4. If soap is wet, it will lather the same as before. The soap will work perfectly fine
Explanation First, you are heating the soap, which softens it. Second, you are heating the air and water trapped inside the soap, causing the water to vaporize and the air to expand. The expanding gases push on the softened soap, causing it to expand and become a foam. When you microwave Ivory, the appearance of the soap is changed, but no chemical reaction occurs. This is an example of a physical change. The microwave puts energy into the soap, water, and air molecules, causing them to move faster and further away from each other. The result is that the soap puffs up. Other brands of soap don’t contain as much whipped air and simply melt in the microwave
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Materials -
Clear bottle Baby oil Water Food coloring Alka-Seltzer
Procedure 1. Fill the clear bottle about 1/8 full with water 2. Fill the rest of the bottle with baby oil until nearly full 3. Slowly add drops of food coloring into the bottle. Notice how they sit on the oil and then gradually burst into the water 4. When the food coloring has mixed with the water, break up an Alka-Seltzer and drop a few pieces in 5. When the reaction has stopped, drop in more Alka-Seltzer until you feel like stopping
Explanation The oil has is lighter than water and therefore stays on top of it. When we drop the Alka-Seltzer in, it’s heavy and sinks down. When it goes through the oil, some of the oil sticks to it and goes into the water. The AlkaSeltzer fizzes in the water and the oil wants to go back up to the top, so it forms bubbles.
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Materials -
4 lemons 2 stiff, uncoated copper wires – 18 gauge 4 paper clips An LED light bulb that requires less than 1.5 V to light or an ammeter (measures amps) 6 – 8 inches thin copper wire or 5 alligator clips
Procedure 1. Prepare the lemons by rolling them between hands or on a table to create juice inside. Push a piece of the stiff copper and a paper clip into each lemon. 2. Use the thin wire or alligator clips to connect the lemons in a circuit. Connect a stiff wire with a paper clip each time. 3. Connect the free ends of the wires to the end of the terminals and see what happens. Note: If everything is hooked up and it’s not working, try switching the wires and terminals on the light bulb.
Explanation Because the lemon juice has acid in it, it helps the movement of negatively charged particles to move from one piece of metal to another. If the metals were the same, the push would be equal and nothing would flow. But by having two different metals, the particles get pushed harder in one direction than the other.
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Materials -
2 – 4 eggs 2 – 4 Clear containers Vinegar Plastic spoon
Procedure 1. 2. 3. 4.
Place one egg in each container Fill the container with vinegar so that it covers the egg and let it sit for a few days After a few days, carefully remove the eggs with a plastic spoon Try to bounce them, starting off very low (1 inch) and moving higher. Have the kids guess when they think each egg will break
Explanation The calcium on the egg shell reacts with the acetic acid in the vinegar and the vinegar is able to eat away at the shell, leaving a smaller, rubbery egg. The outside of the egg is still a little fragile though, and will break when dropped from a certain height.
Hint: See what happens if you hard boil one egg before putting it in the vinegar Hint: Make this into a competition – make teams and see whose egg can survive the biggest drop
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Materials -
Cornstarch Water Plastic mixing bowl or bucket (deeper = better) Spoon
Procedure 1. In the plastic mixing bowl, combine water and cornstarch to form a mixture that looks like heavy whipping cream and has the consistency of honey. Play around with the ratios. 2. After making your mixture, gently lay your hand on the surface of the cornstarch-water mixture. You should notice that your hand sinks in the mixture like you would expect it to do. Move your hand through the mixture, slowly first and then trying to move it really fast. Was it easier to move your hand slowly or quickly through it? 3. Submerge your entire hand and try grabbing a handful of the mixture and pulling your hand out quickly. Then try again, this time relaxing your hand and pulling it out slowly. Did you notice a difference? 4. Try punching the cornstarch-water mixture. (Be careful not to hurt yourself on the bowl!) Make sure to hit the substance hard and pull your fist back quickly. Did the substance splatter everywhere or did it stay put in the bowl?
Explanation Both this mixture and quicksand change consistency depending on what type of force is applied. It is liquid when the movement is slow, hard when the movement is fast But don’t worry about sinking in quicksand! Humans only go about chest deep because they are less dense than the quicksand – lying on your back will help you float to the edge and get out! But if your foot is stuck, relax and move it very slowly so that the quicksand acts more like a liquid.
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Materials -
Whole milk, 2% milk, or half & half Food colouring Cotton swabs Dish soap (Ivory works much better than Sunlight) 2 plates (paper works nicely)
Procedure 1. Pour milk in the plate to completely cover the bottom. 2. Add one drop of each of the four colors of food coloring to the milk. Place them around the plate but not touching each other 3. Now dip the cotton swab in soap and gently place by one of the drops. 4. Try placing the cotton swabs at different points on the plate. 5. Try putting drops of soap straight from the bottle. Try laying the soapy cotton swap on the edge.
Explanation Milk is mostly made out of water but it also contains vitamins, minerals, proteins, and tiny droplets of fat. The fats and proteins are sensitive to changes in the milk. Dish soap, because of its bipolar characteristics (polar on one end, non-polar on the other), weakens the chemical bonds that hold the proteins and fats in solution. The soap’s polar end dissolves in the water and its other end attaches to a fat globule in the milk. The molecules of fat roll around in all directions as the soap molecules race around to join up with them. During all of this, the food coloring molecules are bumped and shoved everywhere, which makes it easy for us to see all of this going on. Eventually, all of the soap will have partnered with the fat and it will no longer happen.
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Materials -
4 clear sealable containers ½ cup water ½ cup vinegar ½ cup club soda ½ cup clear liquid soap 3 teaspoons baking soda A dash of salt for each container A dash of pepper for each container
Procedure 1. Fill each container with one of the four liquids; label each container 1-4 and take note of which is full of which liquid (do beforehand so the kids don’t see) 2. Pass around the container to let them look which is the water – don’t open or shake them! 3. They will be able to rule out the soap because it’s too thick to be water 4. Open the other 3 containers and put a little pepper in each one. It should float on all of them, so you can’t rule any out 5. Sprinkle a bit of salt into each of the containers. It should sink or dissolve in 2 containers but will react with the club soda, ruling that one out 6. Add baking soda to each of the last two containers; it will react with the vinegar and rule it out, leaving the water Hint – Set clear boundaries beforehand for the kids not to shake or open the containers! Hint – Pour the club soda right before the start or else it might not react with the salt Hint – The baking soda will react with the club soda if it hasn’t been eliminated, so make sure to do the salt beforehand to avoid confusion
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