Castle Challenge Teacher Instructions (First Third Grade) The set of experiments explores the concept of surface tension. Students are asked to help Prince Charming save his princess from the castle by testing different variables. This experiment is set up in 3 sections so that it can be split up over a few days or done all at once. Surface Tension is the force liquid molecules exert on one another creating a tightly stretched skin across the surface, which allows for things like water bugs to walk on water! Total Time: 1 hour + 15 minute prep Materials per group: 1 plastic bowl 1 small cup of pepper 2 drops of dish soap (in a small cup) 1 Q-tip 1 cup of quicksand (prepared ahead of time) Water 1 green food coloring 1 tablespoon of borax (in a small cup) 1 bottle of glue 1 popsicle stick 1 spoon 4 plastic cups Preparation: (15 minutes) For the first section of this experiment you should make the quicksand ahead of time. 1. Pour one cup of water into a medium re-sealable container (I recommend that you do not use a plastic bag because it becomes hard to close and the kids can t play with it as well.) 2. Add 2 cups of cornstarch 3. Add 5 drops of yellow food coloring 4. Mix well (can take about 10 minutes) 5. After the solution is mixed well cover the container Castle Challenge Kayla Erf January 10, 2012 1
This experiment is messy! On the day of the experiment you may need to mix the quicksand a second time because the cornstarch tends to settle. You can either separate your quicksand into a small cup for each group or do the demonstrations yourself and have them watch. 1. Split the kids up into small groups (3 or 4) 2. For section 1 each group is given: A cup of quicksand A cup of water The Student Instructions Packet 3. The procedure is as follows 1. Lower one finger slowly into the water 2. Lower the another slowly into the quicksand 3. Pull them both out quickly 4. Tap the water quickly with one finger 5. Tap the quicksand quickly with another 4. Have students complete the first section of the worksheet depending on their age you may or may not want to discuss the results as a group. a. Discussing it as a group worked well with 2 nd graders 5. Explain that: This quicksand is known as a Non-Newtonian Fluid because it has the properties of both a liquid and a solid. This is because the cornstarch that we added to our water increases the surface tension of the water. Water bugs are the only thing that can glide easily across water but if we had a big enough tub of this quicksand any of you could walk across the water as long as you walked quickly and kept moving!! Surface tension can be changed by several factors including heat. This is the reason that your hand sinks in the quicksand and that you would sink if you didn t keep walking! Your body is warm and so it heats up the liquid and you sink! 6. What would they advise Prince Charming to do? 7. For Section 2 each group is given A cup of pepper A bowl of water A Q-tip Dish soap Food coloring 8. The procedure is as follows Castle Challenge Kayla Erf January 10, 2012 2
1. Drop 1 drop of food coloring into the swamp to make it a cool color 2. Add 5 pinches of pepper monsters to your swamp 3. Touch a clean finger to the surface of the swamp (it is important that the finger not have any cornstarch mixture on it) 4. Take a Q-tip and dip it into the soap 5. Lightly touch the soapy Q-tip to the surface of the water 9. Have students fill out the second section of the worksheet 10. Explain that Surface tension is like an extremely thin skin that is stretched across the surface of water. When you add soap to the water it breaks the surface tension and the fragile water bubble spreads out forcing the pepper monsters to the edges. 11. For Section 3 each group is given 1 tablespoon of borax Green food coloring 1 bottle of Elmer s glue 3 plastic cups (2 filled with water) 1 plastic spoon 12. The procedure is as follows: 1. Add the borax to one cup of water, mix well 2. In a separate cup pour 1 inch of glue (you may want to draw a line on the cup ahead of time) 3. Add 3 plastic spoons of pure water to the glue 4. Add 4 drops of green food coloring to the glue, mix well 5. Add 4 plastic spoons of borax water to the glue mixture making sure to get some of the powder down at the bottom as well! 6. Mix well, this could take a while 13. Have students fill out the worksheet separately and then decide as a class which type of dragon it was using the table. Optional: Further experiments: Compare the cornstarch and water goo to the goo you made in section 3, what properties are the same & which are different? Which has a higher surface tension? References: Goo Recipe Number 1, http://littleshop.physics.colostate.edu/try%20at%20home/ goorecipeone.htm, January 10,2012 Pepper And Water Science Magic Trick, http://chemistry.about.com/od/chemistrymagic/a/peppertrick.htm, January 10, 2012 Make Your Own Slime, http://www.sciencebob.com/experiments/polymer.php, January 10, 2012 Castle Challenge Kayla Erf January 10, 2012 3
Name Date Student Instructions Castle Challenge (1st 3rd Grade) Prince Charming needs your help! He is trying to save his princess from the tallest tower of the tallest castle but he is facing some obstacles! In order to make it up to the castle tower he has to get past quicksand, pepper monsters and a scary dragon! In this experiment you will learn about surface tension and how it can help Prince Charming save his princess! Quicksand Prince Charming cannot figure out a way to get across the quicksand without sinking because he doesn t understand surface tension! It is up to you to help him get across! You have two containers in front of you, one with quicksand and one with water. Follow the instructions below 1. Lower one finger slowly into the water 2. Lower a different finger slowly into the quicksand 3. Pull them both out quickly 4. Hit or punch the water (quickly but not too hard) 5. Do the same thing with the quicksand Fill in the table below by putting a check in the appropriate box: Test with Water Softly lowering Rapidly removing Quickly hitting My hand got wet My hand stayed dry Test with Quicksand Softly lowering Rapidly removing Quickly hitting My hand got wet My hand stayed dry Castle Challenge Kayla Erf January 10, 2012 4
Put a check next to each property that the quicksand has: Properties of Liquid Takes the shape of its container Flows or can be poured Has a volume Cannot be cut Cannot be squished Properties of a Solid Has a definite volume Has a definite shape (without a container) Does not flow or run Can be broken into smaller pieces Is the quicksand a liquid or a solid? Liquid Solid Both Neither What would your advice for Prince Charming be? Water and Pepper Thanks to you Prince Charming has crossed the mote of quicksand!! However, next he will have to face a swamp of pepper monsters. In order to help Prince Charming do this we need to create a swamp of pepper monsters to test our ideas! 1. Pour water into a plastic bowl 2. Add 1 drop of food coloring to make your swamp a cool color! 3. Add 5 pinches of pepper monsters into your swamp 4. Touch your cleanest finger to the surface of the swamp Are the pepper monsters scared away? Castle Challenge Kayla Erf January 10, 2012 5
Yes No What would happen to Prince Charming if he tried to swim across? 1. Dip a Q-tip into a cup of dish soap 2. Lightly touch the Q-tip to the water s surface When you added soap to the surface of the swamp what happened? Surface Tension: Every liquid has surface tension. Water s surface tension is very thin and so the soap molecules easily break it. Before the surface tension is broken the surface looks like a bubble. When you touch soap to the water it is like sticking a pin into that tightly stretched bubble and the water underneath spreads out like a puddle. This affects the pepper monsters floating on top! Castle Challenge Kayla Erf January 10, 2012 6
Dragon Goo: Prince Charming has found some goopy green goo that he thinks came off of the dragon living inside the castle. He wants to know what kind of dragon it is so that he can have the right sword to fight him. But he needs your help! We will recreate the goopy green goo following Prince Charming s instructions and then compare it to the table of Dragon Goo to find out which dragon it is. 1. Fill one cup with water and add a tablespoon of Borax powder. Stir it. 2. In a separate cup pour about 1 inch of glue. 3. Add 3 spoonful s of pure water to the glue and stir 4. Add 4 drops of green food coloring to the glue and stir well. 5. Add 4 spoonful s of the borax water to the glue and stir it. At this point what is the consistency of your goo? Thin Thick Could you pick it up and stretch it? Yes No Can you play with it without it dripping? Yes No Compare your answers to this chart: Dragon Type Thickness Color Stretchy Drippy? Hungarian Horntail Thick Green No Yes Swedish Short Snout Thick Green Yes No Norwegian Ridgeback Thick Blue Yes Yes Castle Challenge Kayla Erf January 10, 2012 7