Handbook of Household Science Activities

Transcription

1 Handbook of Household Science Activities For Families with Children Grades K-2 By Marissa Riedel and Stephanie Walczak

2 Table of Contents Introduction 3 Chemistry Experiments Baking Soda and Vinegar Volcano.5 Blow up a Balloon.7 Bubble-Powered Rockets 9 Density of Liquids.11 Giant Bubbles.13 Homemade Ice Cream...15 Lightning In Your Mouth...17 Make a Penny Shiny..19 Mentos and Diet Coke Geyser..21 New Newtonian Goo.23 Red Cabbage Chemistry 25 Physics Experiments Brazil Nut Effect 29 Cartesian Divers 31 Egg in a Bottle.33 Electrophorus and the Leyden Jar.35 Exploring Gravity 38 Biology Experiments Blind Spot 41 Earthworms.43 Ocean in a Bottle 45 Twister in a Bottle 47 Household Experiment Resources..49 2

3 Introduction The Handbook of Household Science Activities was created for families with children grades K-2 who wish to explore the wonders of science at home. All of the activities included in this handbook make use of only commonly used household items and can be completed in under half an hour. Every activity includes an explanation of the experiment, some discussion material for the entire family to consider, and an additional resource that is helpful for finding out more in-depth information about each experiment. The Handbook of Household Science Activities aims to get children and their families excited about science, while introducing many basic concepts central to the study of chemistry, physics and biology all without even leaving home! 3

4 Chemistry Experiments! 4

5 BAKING SODA AND VINEGAR VOLCANO Materials: Small paper cups Masking tape Scissors Baking soda Vinegar Liquid dish soap Food coloring Cookie sheet Learning Objective: To discover what happens when baking soda and vinegar are combined. Procedure: 1) Place one rounded teaspoon of baking soda in the bottom of one of the small plastic cups. 2) While working over a cookie sheet, create a volcano by stacking the small paper cups on top of each other after cutting a hole in the bottom of each cup to be stacked. Be sure to tape your volcano together - and be creative! 3) In a separate cup, fill the cup half full with vinegar. Add one drop of food coloring and two drops of liquid dish soap to the vinegar and mix the solution together. 4) Pour the vinegar solution inside your volcano and watch it erupt! 5

6 Why it Works: When baking soda and vinegar are combined, a chemical reaction occurs. Vinegar, which is acetic acid (CH 3 COOH), reacts with the baking soda, which is sodium bicarbonate (NaHCO 3 ), to form an unstable molecule called carbonic acid (H 2 CO 3 ). Since the carbonic acid is unstable, it immediately breaks up into carbon dioxide (CO 2 ) and water (H 2 O). The bubbles that make the volcano erupt are due to the carbon dioxide (CO 2 ) that is formed when the vinegar and baking soda are mixed! CH 3 COOH + NaHCO 3 H 2 CO 3 CO 2 + H 2 O Discussion: Come up with a definition of a chemical reaction. Would changing the starting amount of the vinegar, baking soda, or both, affect the size of the volcano eruption? If vinegar and baking soda are the only two materials needed to make a volcano eruption, why is liquid dish soap added to the mixture? 6

7 Materials: Rubber balloon Long-necked bottle Baking soda Vinegar BLOW UP A BALLOON Learning objective: To learn more about the product of the chemical reaction between baking soda and vinegar, carbon dioxide (CO 2 ). Procedure: 1) Pour one-fourth cup of vinegar into a dry, long-necked bottle. 2) Put 2 heaping teaspoons of baking soda into the balloon. 3) Then, stretch the opening of the balloon over the mouth of the bottle and tap the baking soda into the bottle and watch the balloon inflate! Why it Works: When the vinegar and the baking soda come together, they undergo a chemical reaction and produce carbon dioxide (CO 2 ). Go to the Why it Works section under Baking Soda and Vinegar Volcano for a more complete explanation. 7

8 Once carbon dioxide is produced, it rises up and out of the bottle and into the balloon because carbon dioxide has a lower density than air, and therefore rises. The balloon expands as more and more carbon dioxide is formed from the chemical reaction with no where else to go! Discussion: What happens to the size of the balloon if you change the amount of vinegar and/or baking soda that is used? One principle of chemistry is that matter can not be created, or destroyed. In other words, the amount of matter that is used to start a chemical reaction must be the same as the amount of matter left at the end of the reaction. So, how is it possible that the balloon inflates during the reaction? 8

9 BUBBLE-POWERED ROCKETS Materials: Plastic 35mm film container with lid Alka-Seltzer tablets Water Eye protection Learning Objectives: To introduce the term chemical reaction and discover why this chemical reaction takes place. Procedure: 1) Find a level-launching surface (outside works best) and put on protective eyewear. 2) Fill the film canister* between one-fourth and one-third full of water. 3) Drop a piece of an Alka-Seltzer tablet into the film canister and quickly close the lid tight. 4) Place the film canister, lid-side down, on the firm, level-launching surface that was chosen. 5) Step back and watch the film canister turn into a rocket! 9

10 * Before filling the film canister with water, feel free to make the film canister more rocket-like in appearance using paper, tape and crayons. Why it Works: Sometimes when two materials are combined (such as water and an Alka-Seltzer tablet), a chemical reaction occurs. When water and Alka-Seltzer is combined, a gas called carbon dioxide (CO 2 ) is formed, which creates lots of bubbles inside the film canister. Since the bubbles and gas have no where to go inside the film canister, the pressure inside the canister increases. As a result of the increased pressure inside the canister, the lid of the canister pops off, releasing the pressure, and as all the carbon dioxide escapes the rocket is propelled into the air. Discussion: How is the bubble-powered rocket similar and different to a real rocket that goes into space? What happens when different amounts of water and different amounts of the Alka-Seltzer tablet are used to set of the rocket? Is there a certain ratio of water to Alka-Seltzer tablet that works best? 10

11 Materials: One tall, clear glass Honey Light Karo syrup Liquid dish soap Water Vegetable oil Rubbing alcohol Food coloring DENSITY OF LIQUIDS Learning Objective: To explore density and understand why one substance may be more, or less dense than another. Procedure: 1) Measure out one-half cup* of each liquid and use the food coloring to color all of the liquids except for the honey and the vegetable oil. 2) Pour each of the liquids slowly into the tall, clear glass. If possible, try not to let the liquids touch the side of the glass while pouring them. 3) Watch as the liquids separate out into various layers! * The amount used for each liquid may have to be adjusted depending on the size of the glass being used. 11

12 Why it Works: Even though the same amount of each liquid was measured out and used, each of the liquids has a different density causing the more dense liquids to sink to the bottom of the glass and the less dense liquids to float to the top of the glass. Density refers to how tightly the molecules of a substance are packed together. A substance with a high density has molecules that pack very tightly together, and a substance with a low density has molecules that do not pack together tightly and may not even be touching each other! Discussion: What would happen if the liquids were added to the glass in a different order? What would happen if different amounts of the liquids were used? Liquids, solids and gases all have densities associated with them. Look around and try to determine what materials have a high density and what materials have a low density. Also, think about a time when the effects of density were observed in nature. 12

13 GIANT BUBBLES Materials: Dawn dish soap (not antibacterial) Distilled water Hula Hoop Children s swimming pool Glycerin (optional) Learning Objectives: First, to demonstrate the properties of water (mainly surface tension) and to begin to understand why bubbles will only form when water is added to soap. Also, to look at water molecules on the molecular level. Procedure: 1) To make the bubble solution, mix 5 gallons (19 liters) of distilled water with 10 cups (2 ½ liters) of dish soap. * 2) Allow the bubble solution to sit overnight before using it. 3) To make the giant bubbles, place the hula hoop at the bottom of the swimming pool and have one or two kids remove their shoes and step into the swimming pool in the center of the hula hoop. 4) Very slowly, pull the hula hoop straight out of the pool and over the kids head. 13

14 * For stronger bubbles, add 1.2 L (5 cups) of Glycerin to the solution. Why it Works: Bubbles form due to the surface tension of water. Water is made up of two hydrogen atoms and one oxygen atom. Every water molecule is electrically balanced, but has an uneven separation of charges. As a result of electrical opposites attracting, water molecules next to each other form a tight bond; one molecule s negative end (oxygen atom) is held by the positive end of another molecule (hydrogen atom). On the surface of the pool, these molecules form an extremely tightly-knit group, almost skinlike, called surface tension. Water alone will not make bubbles because the surface tension is too strong, but adding soap reduces the surface tension. Discussion: How big of a bubble can you make? Do you think using a different amount of dish soap makes a difference? 14

15 HOMEMADE ICE CREAM Materials: Sugar Milk or Half & Half Vanilla Salt Pint-sized Ziploc bag Gallon-sized Ziploc bag Ice cubes Learning Objectives: To find out what happens when salt and ice are combined and watch milk turn into homemade ice cream in minutes. Procedure: 1) Fill the gallon-sized Ziploc bag half full with ice cubes and add six tablespoons of salt to the bag. Seal the bag. 2) Put one-half cup milk, one-fourth teaspoon vanilla and one teaspoon sugar into the pintsized Ziploc bag* and seal it. 3) Place the small Ziploc bag inside the large Ziploc bag and reseal the large Ziploc bag. 4) Shake the large Ziploc bag until the mixture in the small Ziploc bag thickens into cream. This takes around seven minutes. 15

16 5) Remove the small Ziploc bag from the large Ziploc bag. Carefully open the small Ziploc bag and enjoy the ice cream! * Cocoa, sprinkles or other ingredients can be added for flavored ice cream. Why it Works: When the salt comes into contact with ice in the large Ziploc bag, the freezing point of the ice (usually 32* F) is lowered. So, when the salt comes into contact with the ice, it causes the ice to melt. As the ice in the large Ziploc bag melts, it draws much of the heat from the ice cream mixture, causing the mixture to cool down and become cream quickly! Discussion: Why is salt put on the roads in the winter? As more salt is put onto a region of ice, the freezing point of the ice becomes lower and lower. So, what would happen if more, or less, than six tablespoons of salt was added to the large Ziploc bag? 16

17 LIGHTNING IN YOUR MOUTH Materials: Wint-O-Green Mint Life Saver Dark room Mirror/Partner Learning Objective: To introduce the concepts of positive and negative charges protons and electrons. Procedure: 1) Go into a dark room and let your eyes adjust for a few minutes. 2) While looking at a partner, or into a mirror, chew on the Wint-O-Green Mint Life Saver with your mouth open. Chew the mint quickly for the best result. * 3) Look for sparks of light as your partner chews on the mint. * The same result can be achieved by placing the mint on a hard surface and breaking it with a hammer. Why it Works: The light given off by the Wint-O-Green mint is also known as triboluminescence. When the crystalline sugars of any sugary candy are crushed, some electrons are forced out of their atomic fields. These free electrons then bump into nitrogen molecules in the air, transferring some of their energy 17

18 onto the nitrogen molecules. The nitrogen molecules become excited from the added energy and in order to get rid of the energy, the nitrogen atoms emit a small amount of visible light! In addition to giving off visible light, the nitrogen atoms also give off a bit of non-visible light known as ultraviolet light. Wint-O-Green mints are special because they contain a chemical called methyl salicylate which absorbs the ultraviolet light given off by the nitrogen atoms in the air and re-emits it as more visible light! Discussion: Knowing that small sparks of visible light can be given off when an electron is displaced from its orbit in an atom, discuss any possible explanations for why sparks given off during a shock, or when two rocks are ground against each other. 18

19 MAKE A PENNY SHINY Materials: Vinegar Table salt Old, dirty penny Tweezers Learning Objectives: To learn about a chemical reaction, and the difference between acids and bases. Procedure: 1) Mix two parts of vinegar with one part of salt in a cup. 2) Dip the old, dirty penny into the cup using a tweezers and hold the penny submerged under the solution for ten seconds. 3) Remove the penny from the cup and it will look shiny again! Why it Works: The vinegar and the salt that were mixed together in the cup are acidic, and the acidic properties of the two were used to dissolve all of the gunk off of the penny that made the penny look dirty. Acids are positively charged ions (meaning they have more protons than electrons), while bases 19

20 are negatively charged ions. Acids often taste sour and can conduct electricity. Bases on the other hand taste bitter, and can also conduct electricity! Discussion: Are there any other items that you could use a vinegar and salt solution to make shiny? What other cooking ingredients could possibly be used to clean up a dirty penny? Before After 20

21 MENTOS AND DIET COKE GEYSER* * Use what you have learned in the previous experiments contained in the Chemistry section to make sense of the Mentos and Diet Coke Geyser. Materials: Roll of mint Mentos 2 liter bottle of Diet Coke Learning Objectives: To make a huge eruption using Mentos and Diet Coke and consider the reasons why such a huge eruption is created. Procedure: 1) Go outside and find a flat surface for the geyser. 2) Carefully open the 2 liter bottle of Diet Coke and place the bottle onto the flat surface so that it will not tip over. 3) Unwrap the entire role of Mentos and drop all of the Mentos into the bottle of Diet Coke at the same time. Spectators should stand back. Step away from the bottle of Diet Coke quickly after dropping the Mentos into the bottle. 4) Watch as the geyser erupts! Why it Works: It is still debated why such an incredible eruption occurs when Mentos are dropped into a bottle 21

22 of Diet Coke. According to the popular Discovery Channel TV show Mythbusters, the caffeine, potassium benzoate, aspartame, and carbon dioxide (CO 2 ) gas contained in the Diet Coke, and the gelatin and gum arabic ingredients of the Mentos, all contribute to the eruption effect. It is also thought that the physical structure of the Mentos is the most significant cause of the eruption. The surface of the mint Mentos is littered with many small holes which allow CO 2 bubbles to form very rapidly and in great quantity causing the huge eruption of foam. Discussion: Even though the details of the Mentos and Diet Coke geyser are not completely known, try to explain the eruption in terms of the chemical reaction, density and air pressure changes occurring in the Diet Coke bottle and the local atmosphere. 22

23 Materials: Cornstarch Water Food Coloring Large mixing bowls NEW-NEWTONIAN GOO (OOBLECK) Learning Objectives: To demonstrate the different states of matter solids, liquids and gases, and to discuss what properties make something a solid or a liquid. Also, to discover how some substances behave like a solid and a liquid at the same time, and to teach kids the difference between Newtonian and Non-Newtonian substances. Procedure: 1) In a bowl, combine one part water with twoparts cornstarch. 2) Use hands to stir the cornstarch and water mixture together. 3) Add more water if the mixture is too thick, and add more cornstarch if the mixture is too thin. 4) Add a few drops of food coloring and experiment with the Oobleck! Why it Works: The mixture of cornstarch and water acts both like a solid and a liquid at the same time. A Non- 23

24 Newtonian fluid is a fluid that defies Isaac Newton s law of viscosity. Viscosity is the measurable thickness or resistance to flow in a fluid. Newton stated that the viscosity of a fluid can be changed only be altering the fluid s temperature. Thus a Non-Newtonian fluid has the same dependence on temperature, but its viscosity can be changed by applying pressure. So, when you squeeze the goo between your hands, its viscosity increases so it acts like a solid. When you open your hand and release the pressure, the goo behaves like a liquid. The cornstarch and water mixture will not remain mixed forever; eventually they will separate over time. Therefore, one should place the mixture in a Ziploc bag and dispose of it in the garbage rather than pouring it down the drain. Discussion: What happens if you add more cornstarch to your Oobleck? What about if you add more water? 24

25 RED CABBAGE CHEMISTRY MAGIC CABBAGE Materials: Fresh red cabbage Pot, stove and water White paper Blender Strainer Clear drinking glasses Vinegar Baking Soda Test substances (Lemon juice, milk, laundry detergent, etc.) Learning Objectives: Introduce the terms acid and base, and to discover how one can classify something as an acid, a base or neutral. In addition, discover what it means to be an indicator and learn how to make an acid/base indicator using cabbage juice. Procedure: 1) Place approximately two cups of red cabbage in a blender. Cover the red cabbage with boiling water and blend it. 2) Strain out the plant material to obtain a purplish colored liquid. This liquid is at a ph of 7. 3) Set up three glasses side by side on top of a white piece of paper. Fill each glass half full with cabbage juice. 25

26 4) In the first glass, add a little vinegar and stir. Notice the color change to red. Vinegar is an acid with a ph less than 7. Therefore, all acids will change the cabbage solution from purple to red. 5) In the second glass, add a spoonful of baking soda. Baking soda has a ph greater than 7. Therefore all bases will change the cabbage solution from purple to green. 6) Keep the first three glasses as a reference for neutral (purple color), acidic (red color) and basic (green color) solutions. 7) In separate glasses, try adding your own test substance to a small amount of cabbage juice and note the color change to determine if the test substance was neutral, acidic or basic. Why it Works: The red cabbage juice is called an indicator because it shows us something about the chemical composition of other substances. Purplish cabbage juice turns red when it is mixed with something acidic, as was demonstrated using vinegar, and turns green when mixed with something basic, such as the baking soda. No color change indicates a neutral test substance. Discussion: What would happen to the color of the cabbage juice if more than one base or acid is mixed together in the cabbage juice? Be careful: some acids and 26

27 bases such as vinegar and baking soda react to create an eruption. 27

28 Physics Experiments! 28

29 BRAZIL NUT EFFECT Materials: Marble Empty transparent plastic jar with a lid Cornmeal, salt or sand Learning Objective: To discover the physics principle known as the Brazil nut effect. This is the name given to a phenomenon in which the largest particles end up on the surface when a granular material containing a mixture of objects of different sizes is shaken. Procedure: 1) Put the marble in the jar. 2) Add cornmeal, salt or sand to the jar until it is half to two-thirds full. 3) Seal the jar and then shake it up and down. 4) It may take a while, but eventually the marble will rise to the top! Why it Works: You would expect something denser than cornmeal, salt, or sand to stay at the bottom of the jar. Instead, when you shake the jar, both the cornmeal and the marble move up and down, and a bit of the cornmeal fills in the space below the marble before it can fall back to its original position. Once the marble reaches the top of the heap, it gets buffeted 29

30 around and sometimes falls just below the surface. But keep shaking, and it will resurface. Discussion: Try this experiment with other objects, such as M&M s and see what happens. What happens if you use more than two different types of substances in the jar? 30

31 Materials: Small paper clips Small rubber bands Plastic straws Empty 2 liter bottle Water CARTESIAN DIVERS Learning Objective: To introduce the topics of density, bouncy and compression. Procedure: 1) Fold a straw in half and fasten it with a rubber band. Wrap the rubber band several times around the ends of the straw to hold them together. 2) Fill the 2 liter bottle with water. 3) Add weight (paper clips) to the diver. Hook the paper clips to the rubber band holding the straw together. Do this until the diver is almost all the way submerged in the water, but not quite, when placed in the 2 liter bottle of water. 4) Twist the cap of the bottle on. The diver will sink when you squeeze the sides of the bottle and rise when you let go. 31

32 Why it Works: When the sides of the bottle are squeezed, water is forced into the empty space within the diver. As a result of this pressure, the air is compressed and the extra water makes the diver denser than water. Therefore, the diver sinks. Once the pressure on the sides of the bottle is released, the air inside the diver expands to its original size which causes the water to be forced out. As a result, the diver becomes less dense than water and therefore floats. Discussion: Does anything happen to the diver if the bottle of water is not full, or if the diver does not have the proper weight on it? 32

33 EGG IN A BOTTLE Materials: One peeled, hard-boiled egg Plastic or glass bottle with an opening slightly smaller than the egg Large bowl of hot water Large bowl of ice water Learning Objective: To get an egg in a bottle using air pressure. Procedure: 1) Put the bottle in the bowl of hot water for about five minutes. 2) Then move the bottle to the bowl of ice water. 3) Next, wet the egg and place it pointed side down into the opening of the bottle. 4) The egg will slowly move into the bottle! 5) To remove the egg from the bottle, tip the bottle upside down so the egg is near the opening of the bottle and blow hard into the bottle with your mouth covering the opening. 6) Then point the bottle away from you and the egg will fly out! Why it Works: Hot air expands and cold air contracts. So, when the air inside the bottle is heated is expands and the air pressure inside the bottle increases. When the 33

34 bottle is placed into the cold water, the air pressure decreases and the air molecules get closer together. So, the egg gets sucked into the bottle. When you blow into the bottle, you are increasing the air pressure and the air in the bottle pushes the egg out of the bottle because the air likes to go from an area of high pressure to low pressure. Discussion: Many substances act in the same way as the air in the bottle does. However, one molecule that acts differently is water. What happens when you freeze water? Does ice expand or contract? How could you test this? 34

35 ELECTROPHORUS AND THE LEYDEN JAR Materials: Aluminum pie pan Piece of wool approx. 10cm x 10cm Styrofoam plate and cup Aluminum Foil Adhesive Tape Paper Clip 35 mm film canister 2 inch nail Adhesive Tape Tap Water Static Electricity Source Learning Objectives: Learn about electricity. Procedure: 1) To make the electrophorus, tape the Styrofoam cup top down to the middle of the pie pan to use as a handle. 2) Bend the paper clip so that one end is a base and the other is a horizontal arm. Tape the base of the paper clip to the top of the pie pan next to the cup and hang a small strip of aluminum foil over the horizontal arm. 3) Tape the Styrofoam plate to a table and place the pie pan on top of the plate. 35

36 4) To make the Leyden jar, wrap the bottom two thirds of the film canister with aluminum foil and tape it into place. 5) Push the nail through the top of the canister so that it sticks out about 2 centimeters. Fill the canister most of the way up with tap water and then snap on the canister lid. Leyden Jar Electrophorus 6) Next, charge the electrophorus by rubbing the pie pan over the Styrofoam plate do not discharge it. 7) Hold the Leyden jar by the foil and drag the top of the nail along the edge of the pie pan. Note when the nail touches the pie pan the aluminum foil charge tester flips up and down. 8) Charge the pan and repeat this several times. Discharge the Leyden jar by touching the nail and the foil at the same time. * * You will get a shock but it is not enough to be dangerous. Why it Works: When you rub the pie pan over the Styrofoam plate, it gives the Styrofoam a negative charge. That is 36

37 because the Styrofoam attracts electrons from the pie pan. Since the Styrofoam has a negative charge and the pie pan now has a positive charge, the two will be repelling each other. When you touch the Leyden jar to the pie pan, the protons are transferred into the Leyden jar, charging the Leyden jar. The Leyden jar can be charged until you chose to touch it with your finger, at which point the protons jump through the air to reach your finger, causing the small shock! Discussion: Can you discharge the Leyden jar without touching it? How far away can you do this? Is there a maximum charge your jar can hold? Can you discharge the Leyden jar onto anything else? Can you get a shock by directly touching the pie pan, without using the Leyden jar? 37

38 Materials: Basketball Marble Baseball Bouncy ball EXPLORING GRAVITY Learning Objective: To learn about gravity. Procedure: 1) Take any two balls and hold them at the exact same height in front of you. 2) Drop the balls at the exact same time and watch to see if either of the balls hits the ground first. 3) Try this on all the combinations of balls possible. Why it Works: All of the objects you chose to drop will hit the ground at the exact same time. This is because the only force acting on the balls (or anything for that matter) is gravity, and gravity is constant. So, the weight of the ball does not make a difference as to how fast it falls. 38

39 Discussion: What would happen if you chose to drop a marble and a piece of paper? Can you explain this result? 39

40 Biology Experiments! 40

41 Materials: Piece of white paper Pen BLINDSPOT Learning Objective: To discover the blind spot in each eye. Procedure: 1) On the piece of paper, draw a cross and a circle, as follows. 2) Hold the piece of paper near your nose so that the cross is in front of the right eye and the circle is to the right of the cross. 3) Close your left eye and slowly move the paper away from your nose with looking at the cross. 4) At a certain distance, the circle will disappear - but only if you are looking at the cross! 5) Repeat the experiment on your left eye, but make sure you flip the paper so that the circle is to the left of the cross. Why it Works: In the back of the eye there are many cells called photoreceptors that detect light and allow you to see. However, all of these cells must leave the eye and 41

42 go to your brain and they leave the eye at one place called the blind spot. You can not see anything in the blind spot because there are no photoreceptors there! Discussion: How big is the blind spot? How come you do not notice the blind spot? Try repeating the above experiment but instead of drawing a circle, draw a line with a star in the middle, as shown below. What happens when the star disappears? Why do you think this happens? 42

43 EARTHWORMS Materials: Mustard Powder Empty one-gallon bottle Water Cup or bowl to collect worms Learning Objective: To watch and collect earthworms as they emerge from the ground. Procedure: 1) Pour 1/3 cup mustard powder into the empty 1 gallon container. 2) Fill the container with water and shake. 3) Pour about half of the mustard-water onto the ground. 4) Wait a few minutes and then pour the rest. 5) Watch carefully as worms wiggle their way out of the ground. 6) Collect worms and place them into containers for a closer look. Why it Works: Worms are irritated by the mustard powder so they emerge from the soil. Discussion: Can you identify the worms? 43

44 Is there a way to determine if a worm is young or old? 44

45 OCEAN IN A BOTTLE Materials: Jar or glass/plastic bottle with a lid Hot glue gun Water Vegetable oil Blue food coloring Sand Seashells Learning Objective: To create your own ocean in a bottle to simulate the real ocean. Procedure: 1) In a clean jar, place a few spoonfuls of sand. 2) Add water until the bottle is 1/2 full. 3) Add a few drops of blue food coloring. 4) Add a few seashells for your ocean. 5) Add vegetable oil until almost full. Leave a small space for air at the top. 6) Hot glue the lid onto the bottle. 7) Turn your ocean on its side and watch the waves go back and forth. Watch the sand gently move as the waves go by. Shake up the bottle and watch the sand. 45

46 Why it Works: Some liquids just don't mix. This is because some liquids are denser than others. For example, when oil and water are mixed together the oil always rises to the top because it is a less dense liquid. The two just will not mix. By placing both oil and water in a container and adding a few drops of water-based food coloring, the color will mix with only the water since it is of the same density and not mix with the oil. It will act as a beacon for us to see the separation of the two liquids. As the container is tilted and the water is pulled down by gravity it will slowly move the oil out of its way and flow like waves to the other side of the container. Discussion: Make some comparisons between the ocean in the bottle and the real ocean. Is the ocean in the bottle a good simulation of a real ocean? 46

47 Materials: Bottle with lid Water Vinegar Clear liquid dish soap Glitter (optional) TWISTER IN A BOTTLE Learning Objective: To observe how a vortex (tornado) forms. Procedure: 1) Fill the bottle 3/4 full of water. 2) Put in 1 teaspoon of vinegar and 1 teaspoon of dish soap. 3) Sprinkle in a small amount of glitter (optional). 4) Close the lid and twist the bottle to see a vortex like a tornado form. Why it Works: As you twist the bottle, the water up against the glass is pulled along, but slower than the water in the center of the bottle, due to its friction against the glass walls. The fluid toward the inside takes longer to get moving. But eventually both the bottle and the fluid are spinning as you rotate the bottle. When you stop rotating the bottle, the fluid inside keeps spinning. A mini twister can be seen for 47

48 just a few seconds when the outer fluid slows down and the inner fluids continue to spin rapidly. Discussion: Attempt to explain how a real tornado forms based on the explanation of the twister in a bottle. 48

49 Household Experiment Resources Baking Soda and Vinegar Volcano no.htm gar-volcano Blow up a Balloon Bubble-Powered Rockets first/?cid= Density of Liquids ven-layer-density-column Giant Bubbles ent/giant-bubble-experiment Homemade Ice Cream Lightning In Your Mouth 49

50 Make a Penny Shiny Household-Science-Experiments Mentos and Diet Coke Geyser os_eruption New Newtonian Goo Red Cabbage Chemistry htm Brazil Nut Effect Cartesian Divers 50

51 Egg in a Bottle ience/bottled-eggsperiment. Electrophorus and the Leyden Jar uest/past/upload/pq06-extension1.pdf Exploring Gravity Blind Spot Earthworms Ocean in a Bottle _a_bottle/ Twister in a Bottle 51