“Atoms-for-Kids” by akgame

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									“Atoms for Kids”
Session One Introduction into the microscopic world – Being Scientific A. Discussion: What is the smallest thing that you can see with your eyes? B. Discussion: What is the smallest thing you can see with a microscope? C. Using a simple microscope, have students look at a few items. Include some of the following: yarn, salt crystals, coffee grinds and dead skin. D. In their Science Journals, have students record their observations by drawing pictures and writing some descriptive terms. Be sure to share some of the ideas out loud so that students understand the assignment. II. Everything on earth is made up of smaller things A. Example: Show them a house or other simple structure that is made up of Lego‟s. Even though you see a house, you know that the house is made up of smaller individual parts called Lego‟s. B. Show them another item such as a block of aluminum. Even though you see a block of aluminum, scientists know (and you know now) that the block is made up of smaller individual parts called atoms. (Define: all matter is made up of building blocks called atoms) C. Even though we could see many small things underneath the microscope, we could not see the atoms that make up everything on earth. These atoms are too small to see. III. How do we “see” atoms if they are so small? A. Activity: Provide each student with a sealed brown bag that contains a “mystery object”. Using all of their senses except for sight, have students draw a picture of what the object “looks” like. Based on these observations, (or tests they conduct, such as dropping the bag on the floor) have students guess what the mystery object is. Open the bag to confirm. B. Have students repeat the activity using another bag and mystery object. C. Lesson: Scientists cannot see atoms, but they can create pictures of what they believe the atoms look like by conducting various tests. Atoms are too small for even the most powerful light microscope to see them, so other methods of “looking” at atoms are used.

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Session Two I. Using models A. When something is really big, people make a model of it so that it is easier to look at and study. Can anyone think of an example of something that is really big that is made smaller into a model? (Ex: globe, rocket, car, buildings, etc.) B. When something is really small, people make a model of it so that it is easier to look at and study. Can you think anyone think of an example of something that is really small that is made bigger into a model? (Ex: eyeball, DNA, skeletons, atoms) C. Show them a ping-pong ball. Tell them that this is a good model to describe what an atom looks like. II. Closure: Forming a Hypothesis A. Based on what a model of an atom looks like, what do atoms that make up a solid and liquid look like? How are they arranged? Remember: There are no wrong answers – guess and design an experiment to test the guess.

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Atoms are often arranged in nature A. Show them the ping-pong balls arranged inside of a clear container to illustrate how the atoms look inside of something solid. Tell them that if we could put on super high magnifying glasses and were able to look at a block of gold, we would be able to see the atoms inside of the block of gold and they would be arranged in a similar way. B. Atoms are arranged or organized inside of crystals. Show them the model of the atoms glued together to illustrate how atoms in a crystal look. Have students refer back to the drawings and descriptions that they did last week in their Science Journals. Share descriptions of observations (cube-like).

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Crystals need a starting point or „trigger‟ A. Do crystals grow in nature? Where do crystals grow? Why don‟t crystals grow in everywhere? What do crystals need in nature order to start growing? (they require some sort of trigger called “seeding” or helping the atoms arrange themselves in a organized pattern) B. Ask if anyone has ever grown crystals before. How did they grow them? What were they made out of? How long did it take?

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Growing Crystals Part 1: Epsom Salt A. Each student needs to be given a small plastic petri dish. Label the dish with their name using a small sticker on the side of the dish. B. Students should place a small drop of dish soap in the center of the dish and spread the soap out into a thin film. After the film has been created, students should use eyedroppers to place a small drop of Epson salt solution onto their petri dish. C. Students then fan the drop of solution using a piece of paper. After a few minutes of fanning, the water in the solution will evaporate and the crystallized Epson salt will remain behind. D. Have students record their observations in their Science Journals. Part 2: Crystal Packs A. Pass out a crystal pack to each student. In their Science Journals, have them describe what the packs look and feel like. Share observations. B. Have students click the disk in the crystal pack. Have them watch and feel the pack while the crystal forms. C. Have students click another crystal pack. Make sure that this time the record observations that they make during the crystal formation in their Science Journal. Share the observations with the rest of the class. Look for words like „pattern‟, „design‟, „repeating‟, etc.

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Session Three I. Review: Crystals What did you learn about the atoms inside of crystals? How are they arranged (refer to you Science Journals to help you describe their arrangement based on your observations? Where do they grow? What do they need in order to start growing? II. Growing Crystals - continued A. Give each student a small glass jar. Have them put their names on the jar using a piece of tape placed on the side of the jar. B. With the help of an adult, the pre-made super saturated solution of sugar and water should be poured into individual glass vials. Make sure that there are some sugar crystals at the bottom of each glass vial. Students can add food coloring to their solution at this point. C. Students should hang a string attached to a paperclip into the solution. D. Have students make observations about their crystal solution in their Science Journal. Make sure they include a date. E. Wrap up: What will trigger the growth of the crystals in this solution? III. Student Demonstration: Arrangement of Atoms - Three Phases of Matter Have a small group of students (approximately five) act out what the arrangement of atoms inside of a liquid, solid and gas looks like. Solid: Students lock elbows with one another and move slightly Liquid: Students hold hands with one another and move within limits Gas: Students are not attached to other students – roam freely IV. Surface Tension Definition: When liquid (water) atoms are attracted to one another and cling to one another so as to form somewhat of a barrier. The stronger the surface tension, the more difficult it is to break the barrier. A. Activity One: Have students fill a clear plastic cup to the top with water (bring a pitcher along for pouring). Have them estimate how many pennies they think they can fit into the glass of water before the water runs over the edge. Write their hypothesis down in their Science Journals. Have them test their hypothesis by slowly dropping the pennies down the side of the cup. Discuss their results.

B. Activity Two: Have the students fill their clear plastic cup to the top with water. Have them drop a paper clip into the cup of water and watch it sink. Give them another paper clip and have them place it carefully on the top of the water. Discuss their results (think of water bugs!) Extension: Have students place a small drop of dish detergent on their index finger and carefully dunk their finger in the cup of water as far away as possible from the floating paper clip. Discuss their results. C. Activity Three: Have students fill their clear plastic cups to the top with water. Have them sprinkle pepper on the top of the water. Have students place a small drop of dish detergent on their index finger and carefully dunk their finger in the center of the cup of water. Discuss their results. D. Activity Four: Have students fill their clear plastic cups to the top with water. Give them round plastic lid that they can place over the opening of the cup. While holding the cup of water over the bucket, have the students invert the cup of water – making it upside down with the plastic lid now becoming the base. Slowing, have the students remove their hand that is supporting the plastic lid. The lid should remain “stuck” to the bottom of the cup. Discuss their results. V. Real World Applications: Where do you see examples of surface tension? Why is it important?

Other Possible Activities to Conduct Introducing Phases of Matter IV. Exploring Ooblick: Solid or Liquid? A. Pass out a pre-measured quantity of cornstarch in a plastic cup to each student. (1-cup cornstarch) B. Have students measure out ½ cup cold water and pour into cornstarch C. Using spoons, have students stir the cornstarch and water mixture D. Have students explore the behavior of Ooblick – be sure to place newspaper across the students desks. E. Share observations with the entire class

“Atoms for Kids” Session Four I. Observing Crystal Growth A. Have students observe the growth of their crystals from last week. Have them record three observations in their Science Journals. Review: What did we learn about surface tension last week? Investigation Question: “What do you need in order to make bubbles? a. Student answers will normally include: soap, water and a circular object b. To answer this question, have students perform Procedure Steps Part I (see attachment) c. After performing Part I, discuss their results. You do not need a circular object to blow bubbles, you need an object that is enclosed. Investigation Question: Do different enclosed areas (shape) create different shaped bubbles? A. To answer this question, pass out bendable wire to the students. Allow them to create any shape they imagine and have them blow bubbles. B. Students record their experimental results in their Science Journals. C. Conclusion: The enclosed area can be any shape (triangular, square, etc.) but it will always blow a sphere shaped bubble. Discussion Question: Why do you need soap to blow bubbles? What is it doing to the atoms on the surface of the water (surface tension)? A. Water has a very strong surface tension – the atoms in the water “hold hands” tightly and do not want to stretch far apart from one another. B. Soap actually decreases the surface tension of the water – it allows the atoms to stretch further apart from one another before breaking. Investigative Question: How many bubbles can surround a single bubble? Can bubbles ever form angles? A. Using two Plexiglas sheets, rest one of the sheets on the table and have students place some bubble blowing solution in the center it. B. Using a straw, have the students capture a small amount of bubble solution in the bottom of the straw, tilt and gently blow through the straw. Form as many small bubbles as possible on top of the Plexiglas. C. Carefully place the second piece of Plexiglas on top of the first. What do you see? How many bubbles touch one another? Why so few?

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For an explanation of the above phenomenon, see “When Bubble Meets Bubble” at http://www.exploratorium.edu/ronh/bubbles/bubbles.html

“Atoms for Kids” Session Five I. Review: A. What did we learn last week about surface tension and soap? Why do you need soap (or syrup, etc.) in order to blow large bubbles? How many bubbles walls will touch one another before they break away? Why? The Behavior of Atoms in Extreme Temperatures A. Have a few students “act out” how atoms of a liquid behave that are cold versus atoms that are hot. (This should be a review.) Then have students guess as to what would happen if atoms of a liquid were super cold and super hot. How would it differ from the previous behavior? Extreme Temperatures - For the following demonstrations, a Dewar of liquid nitrogen must be available as a source of extreme cold and a small blowtorch needs to be available a the source of extreme heat. CAUTION: BE CAREFUL WHEN HANDLING THESE MATERIALS DURING THE DEMONSTRATION. KEEP STUDENTS AT LEAST TEN FEET AWAY. WEAR SAFETY GOGGLES AT ALL TIMES. Extreme Heat (Blow Torch @ approximately 900 oF or o482 C) A. Using a ball and loop set, show the students how the solid metal ball will not fit inside of the loop. Using the blowtorch, heat the metal loop with the hottest part of the flame for ~ 30 seconds. Try inserting the ball through the loop (it will fit). Have students explain why it now fits (the atoms have moved farther apart from one another). To re-illustrate the point, now heat up the metal ball and demonstrate how you can no longer slip it in/out of the loop. B. Heat one end of a bi-metallic strip with the blowtorch. One side of the strip will heat faster than the other (two different types of metals) and will cause the strip to “curl”. Have the students explain to you why this is happening. Real world applications: Thermostats in a house are controlled using bi-metallic strips. Extreme Cold (Liquid Nitrogen @ approximately -328 oF or -200 oC ) A. Carefully pour some of the liquid nitrogen from the Dewar into a Styrofoam cup. Submerge a flower (any type) into the liquid nitrogen for about 30 seconds. Have students hypothesize as to what they think will happen to the flower. Take the flower out and slap it against the top of the desk. The flower will shatter. Have the students explain why.

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B. Using the same technique as before, submerge a banana into the liquid nitrogen. After ~ one minute, take the banana out and use it as a hammer to pound a nail into a piece of wood. C. Using the ball and loop from the previous demonstration, ask students to predict what will happen to the ball when it is submerged in liquid nitrogen – will it fit through the loop or not? Conduct a test. D. For an extensive list of other demonstrations to do with liquid nitrogen, see: http://www.physik.uni-augsburg.de/~ubws/nitrogen.html VI. Closing Activity - Have students make ice cream using liquid nitrogen! There are a variety of methods that can be used. Here are just two: A. Give each student two large (32 oz) Styrofoam cups (one inside of another), and a wooden chop-stick (stirring tool). Have them mix the following ingredients inside of the cup: 3/4-cup heavy cream ½ cup whole milk (either chocolate or plain) 1-teaspoon vanilla ½ cup sugar Pour ~ ½ of liquid nitrogen directly into the Styrofoam cup. Have the students vigorously stir the ingredients until the desired texture is achieved (extra nitrogen might need to be added)

B. In a large metal bowl, mix the following ingredients: 2 pints heavy cream 1 bottle Karo clear corn syrup 1 12 oz bag semi-sweet chocolate chips 1 12-oz jar maraschino cherries, drained 1 tsp vanilla extract 3 tsp almond extract Pour liquid nitrogen into the metal bowl and stir vigorously with a wooden spoon until the desired texture is achieved.

“Atoms for Kids” Session Six I. II. Topic: Atoms in a Vacuum Assess Prior Knowledge What do you know about outer space? Can astronauts breathe in outer space? Is there “air” in outer space? Investigative Question: Do atoms behave differently in an area where there are very few atoms versus a lot of atoms? - There are environments that contain very few atoms; we call these environments vacuums. Matter behaves differently in a vacuum. - On Earth we can create an environment like space by using a vacuum chamber and pump. Activity to Answer Investigative Question: A. Have the students pair up and give each pair a different object to test inside of the vacuum. The objects can include a burning candle, a half-way blown up balloon, a dish of water, a small block of wood, a ping-pong ball and shaving cream. B. Students should each create a hypothesis as to what they think will happen to their object inside of the chamber. Have them write down their hypothesis in their Science Journal. C. Have the students sit on the floor surrounding the bell jar and vacuum pump. In turn, each group will share their hypothesis and test their hypothesis using the vacuum chamber.

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V. Results from the Investigation: A. After each test, have the students discuss the results of their test. Help out by asking them probing questions. Ex: “Why did the balloon get larger?” (No atoms were pushing on the outside of the balloon, only the atoms inside the balloon were pushing out and could occupy more space inside of the balloon) B. Give each student two marshmallows placed inside a Ziploc baggie. Put the Baggies in the vacuum chamber and have the kids guess what will happen. (Most will understand by now.) After the marshmallows expand, they will shrink when you remove the lid to the jar. Have the kids eat the marshmallows for extra fun!


								
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