CFL.MadScience.org YouTube.com/KineticKylie

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1 CFL.MadScience.org YouTube.com/KineticKylie

2 Welcome to Mad Science!

3 The Scientific Method 1. Question- What do you want to find out? 2. Observation- What do you notice? 3. Hypothesis (Guess)- What do you think is going to happen? 4. Experiment- Do an experiment to help find the answer! 5. Conclusion- What did you find out? Always try to incorporate the steps of the Scientific Method into your experiments! Experiment: Oil vs Water Cooking oil Water 2 clear glasses or containers Paper clip, piece of cork, candle or other small objects 1. Hold up a glass, ½ full, of cooking oil and a glass, ½ full, of water, and challenge your class to make some observations about the two liquids. 2. Ask your students to hypothesize, or make their best guess, as to what would happen if you mixed the two liquids. 3. Perform the experiment: pour the oil into the water. 4. Discuss the results with your class. Were the results the same as the students hypotheses? What conclusions can they make? Oil and water don t mix! 5. You can reinforce these important concepts by building on the experiment itself. Allow your students to observe different items (e.g. a paper clip, a cork, buttons etc.) and challenge them to develop a hypothesis: Will the object float in water? How about in oil? Test their hypotheses and see what conclusions you can come up with as a class. Water and oil have different densities. Density is the quantity of something per unit measure. In simpler terms, the mass of a substance you have in a certain volume or area. Oil is less dense, which means that it sits on top of the water and the two liquids will not mix.

4 Experiment: Bernoulli s Principle Ping pong balls Bendable straws Hair dryer 1. Give each child a bendable straw and a ping pong ball. Bend the straw to create a 90-degree angle. Ask the children to try to balance their ping pong balls on the short end of the straw. (They will not be successful.) 2. Tell them about Bernoulli s Principle and instruct them to blow through the straw to catch the ball in the lowpressure flow. The high-pressure air around their airflow will hold the ball hovering above the straw. 3. Try it again with the same ping pong ball and a hair dryer. Can you get 2 or 3 balls to float? Daniel Bernoulli discovered that fast moving air creates an area of low pressure. This theory has been used to fly airplanes and study the flight process of birds. This experiment allows the students to discover the fun of air pressure. Experiment: Air is Where? Clear gallon bucket or large aquarium Clear drinking glass Food coloring Paper towel Students use the power of observation and prediction in this experiment which takes an empty glass and demonstrates that an empty glass may not be as empty as it seems. What happens when the glass is turned upside down and placed under water? This simple but effective experiment demonstrates air s ability to take up space. 1. Fill a large clear container with tap water and add a few drops of food color. Place the large container before the class and hold the empty drinking glass in your hand. Have the children observe the contents of the glass and claim there is something in the glass, BUT it is something that you can not see. Let the children make a guess as to what it might be. Explain that there is air in the glass. 2. Crumple a piece of paper toweling (or paper, it does not matter) and place it in the bottom of the glass. Have the students predict what will happen as the glass is placed upside down and pushed under water. Remove the glass and inspect the toweling. (Be sure to keep the glass straight during this whole process.) Discuss the results. 3. Place the glass with the toweling back into the water upside down and make predictions as to what will happen if the glass were tilted to one side. After soliciting responses, tilt the glass while pushing under water. Observe the toweling and compare your predictions. Why did bubbles come out of the glass? (It is because air was escaping and water was able to get in.) Extension Experiments: Float a regular Ping-Pong ball in the large clear container. Challenge the children to get the ball to the bottom of the water without ever touching the ball. What is the secret? Place your cup over the ping pong ball and press the cup and ball under the water. When the cup is pushed to the bottom, the ping pong ball will sit in the cup on the bottom of the tank.

5 Experiment: Density Stacker We know that different things float on water. Something will float on water if it is lighter and less dense than the water. That means that the molecules in the floating objects are not packed as tightly together as the liquid they are floating upon. But, did you know that even liquids can float on each other? Corn syrup Maple syrup Detergent (colored) Water (colored red with food coloring) Vegetable oil 1 empty clear bottle or graduated cylinder (a shampoo bottle works great) 1. Start with an empty bottle and pour some corn syrup into it. Add enough corn syrup to make about a 2 cm (½ inch) layer. 2. Now add some maple syrup. (Add another 2 cm, ½ inch layer) 3. Next add the detergent. (Add another 2 cm, ½ inch layer) 4. Add in the rest of the layers in the order stated. Note: If the bottle is shaken, some of the layers may mix. The layers will return but probably will be missing a few that may have combined. Experiment: Raindrops Wax paper Drinking straws Spray bottle filled with water This experiment lets the children experience the cohesive properties of water. This explains why the raindrops sliding down the window join together to form bigger drops. 1. Give each child a sheet of wax paper and a straw. 2. Spray some water onto each child s wax paper. Use the spray bottle on a fine mist setting. 3. Instruct the children to use their straws to try to blow the water drops together into one big raindrop. Water molecules are attracted to each other. This principle is called cohesion. Water molecules stick better to themselves than they do to the wax paper or the glass on your windows so the drops of water join together to form one big drop.

6 Experiment: Pudding Colors 1 package instant vanilla pudding 500 ml (2 cups) milk Food coloring 3 small bowls How do your other senses affect your sense of taste? This experiment will help you judge whether your sense of sight or smell will change your perception of taste. 1. Mix up the pudding with the milk and split the pudding into 3 or more bowls. 2. Add food coloring to each of the bowls to make them appear to be different flavors (ie: butterscotch, banana, chocolate, lemon etc.). Do this ahead of time so the students do not see that you are altering the pudding. 3. Ask the children to predict the flavor of each of the puddings prior to tasting using their senses of sight and smell. Let them taste from the different bowls and verify their hypotheses. 4. Does appearance have an effect on taste? Experiment: Balloon Blow-up Plastic flask (any other bottle like shampoo bottle, soda bottle, etc) Spill tray or bowl Vinegar Baking soda Balloon Teaspoon Procedure 1. Squirt approximately ¼ cup of vinegar (acetic acid) into your flask or bottle. Place it in the spill tray or bowl to catch any spills. 2. Pour approximately 5mL (about 1 teaspoon) of baking soda (sodium bicarbonate, a base) into the balloon. 3. Carefully, and without spilling any of the baking soda from the balloon, attach the mouth of the balloon to the top of your flask or bottle. 4. Lift the balloon so the baking soda falls into the flask. If it leaks, hold the balloon onto the flask. 5. Watch the balloon inflate, as if by magic. The vinegar and baking soda create a chemical reaction. One of the results is CO 2, carbon dioxide gas, which expands (gets bigger) and blows up the glove. Carbon dioxide is the same gas that humans and other animals breathe out (they breathe in oxygen). Plants, on the other hand, breathe in CO 2 and breathe out oxygen. CO 2 is also found in fire extinguishers, because it pushes oxygen out of the way. Fire, just like us, needs oxygen.

7 Experiment: Magic Mud Small bowl ¼ cup cornstarch ¼ cup water Craft sticks for mixing Lots of newspaper or plastic to cover your work surface WARNING: THIS CAN BE A MESSY PROJECT! Be sure to cover your work surface! 1. Mix equal parts of cornstarch and water in the bowl with the craft stick. NOTE: Mixing can be a challenge and takes some patience. You need to mix slowly so that the molecules do not bond together and firm up. 2. Experiment with the substance you have created. Try rolling a ball in your hand. What happens when you stop rolling? 3. Be sure to dispose of your magic mud in the trash. The students will explore the properties of a non-newtonian fluid. This substance is known as non-newtonian because it does not conform to the typical physical properties of either liquids or solids. Under stress or pressure, like someone squeezing it, the molecules will bond together and it will firm up and act like a solid. If you let go, it will ooze out of your hand and turn into a liquid type substance, because the molecules do not stay bonded. Experiment: Milk Explosions Pie plate or low shallow bowl 3-4 colors of food coloring 1 cup whole milk / 35% cream or canned condensed milk 2-3 drops of dishwashing detergent 1. Pour the milk into your bowl or pie tin. 2. Drip 3 drops of each color of food coloring into the milk, spreading out the drops around the pan. Intersperse the colors around the pan. You will find that the color floats on the surface of the milk. The surface tension holds the color in one place. 3. Drop one drop of detergent into the center of the pan of milk and watch the color explosion occur as the surface tension breaks allowing the coloring to spread. (This is the same way the grease comes off your dishes in the sink.) 4. You can add another drop of detergent when the colors stop exploding. It will repeat 2-3 times. Everything in the world is made of atoms and molecules. That includes water. Water molecules do some very interesting things. If you pour water slowly into a glass, you can actually get the water to go higher than the top of the glass. This is called a meniscus and is created by surface tension. In simple terms, the water molecules like to stick together. This experiment looks at the surface tension of milk.