Teacher: Shelley Wiebe and Laura Friesen Subject: Science Grade: 7
Topic: Heat and Temperature
Curriculum outcome:
Knowledge Outcome 2. Describe the nature of thermal energy and its effects on different forms of matter, using informal observations, experimental evidence and models • compare heat transmission in different materials • describe the effect of heat on the motion of particles; and explain changes of state, using the particle model of matter • investigate and describe the effects of heating and cooling on the volume of different materials, and identify applications of these effects Skill Outcome Initiating and Planning Students will: Ask questions about the relationships between and among observable variables, and plan investigations to address those questions • identify questions to investigate arising from a problem or issue Attitude Outcomes Interest in Science Students will be encouraged to: Show interest in sciencerelated questions and issues, and pursue personal interests and career possibilities within sciencerelated fields
Lesson objective(s):
Students will explore the concept of “particle model of matter” and how it affects their everyday life. They will be encouraged to ask questions and to explore ideas for themselves.
Context/Rationale: The unit of Heat and Temperature takes place at the beginning of the new year. This discrepant event would be used as an introduction to the unit to increase students interest. They will inquire and discover how heat affects different particle matters. Resources/ Materials:
● balloons ● candle ● water ● match ● safety glasses Youtube Video: http://www.youtube.com/watch?v=HK6G4DaFv0 http://www.merriamwebster.com/dictionary http://www.edquest.ca/component/content/article/144
Learning styles & Multiple intelligences:
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visual spatial bodily kinesthetic naturalistic mathematical logical
Time Frame: 50 mins
Introduction:
Timeline:
Anticipatory Set Game: Who Started the Motion Students get into a circle and one student leaves the room. While student is gone decide on a leader who will lead the movement, the movements will periodically change. Student is asked to return and stand in the middle of the circle. From there they will decipher which student is leading the movements. Introduction Introduce: Objectives and Concepts Learning Vocabulary: Step One: Teacher explains definition in student friendly terms (going beyond simply reading the definition from textbook) Step Two: Student explains it to a partner Step Three: Join another partner and physically represent what your word would look like. Scientific Terms: Thermal conduction: the transmission of heat energy by conduction (through matter) ex. copper, water or wood as conductor) solid: Matter in its solid state has particles that are attached to each other in all directions. Resulting in definite shape and volume, very limited in movement and have less kinetic energy. liquid: Particles in the liquid state are only loosely attached to each other and they can easily slip past each other. Meaning liquids can take shape of their container and has definite volume. There is greater range for movement, so liquids have more kinetic energy. gas: Particles of matter in a gas state are not connected to one another. Allowing gas to fill empty spaces of a container, it has no set shape. Gas particles have the greatest movement; therefore, has the greatest kinetic energy. kinetic energy: the energy of movement; particles that make up matter have kinetic energy particle model of matter: The Particle Model of Matter is a scientific description of the tiny particles that make up all things. The key elements in this model are: All substances are made of tiny particles too small to be seen The particles are always in motion The particles have spaces between them When heat is added to a substance, the particles move faster. When heat is lost from a substance the particles move slower. The motion of the particles increases when the temperature increases. The motion of the particles decrease when the temperature decreases Temperature indicates the average energy (speed) of the particles in motion in a substance.
5 mins 10 mins 20 mins
Step One: Procedure 1. For this experiment, the independent variable is whether the balloon is filled with water or not. The dependent variable is what happens to the balloon when it is placed above the lit candle. This is determined by observing the balloon. The constants (control variables) are how much the balloon is inflated and the amount of water in the balloon. 2. Inflate the yellow colored balloon and tie it up. 3. Pour half a cup of water into the blue colored balloon before inflating it to the same size as the yellow color balloon and tie it up. 4. Light up the candle. Be careful when using match sticks to avoid causing fires, or burning yourself. Step Two: Observe and Predict What will happen when the balloons are place on top of the candle? *Do the experiment* 5. Hold the yellow colored balloon on top of the lit candle. Observe and record what happens. 6. Hold the blue colored balloon on top of the lit candle. Observe and record what happens. Step Three: Explain: Why did this balloon pop? And why didn’t the other balloon pop? EXPERIMENT 1. Blow up a balloon just as you normally would and tie it off. 2. Light a candle and place it in the middle of the table. 3. Put on your safety glasses because it's time to pop the balloon. Hold the balloon a foot or two over the top of the flame and slowly move the balloon closer and closer to the flame until it pops. You'll notice that the flame doesn't have to even touch the balloon before the heat melts the latex and it pops. Let's just say you had to prove what you already know. Let's repeat the experiment but this time the bottom of the balloon will have a layer of water inside. 1. Fill the balloon to the top with water – it probably holds a few ounces (60 mL for the scientists) – and then blow it up with air. If you accidentally let go of the balloon before you tie it off, you'll spray yourself and your friends will love it. Just tie off the balloon and get ready for the next step. 2. Slowly lower the waterfilled balloon over the candle and watch as people start to run. Everyone knows that it's going to pop... but for some strange reason it doesn't. If you're very brave, you can actually allow the flame to touch the bottom of the balloon and it still doesn't pop.
3. Remove the balloon from the heat and carefully examine the soot on the bottom. Yes... there's soot and the balloon didn't pop. Before reading the explanation, try to figure out why the layer of water kept the balloon from popping. TAKE IT FURTHER!
Now that you know water will prevent a balloon from popping, try other liquids. Try performing the experiment with juices, sodas, and more. Who knows what will happen? One thing is for sure, you'll find out what liquids are the best conductors of heat! HOW DOES IT WORK? Water is a great substance for soaking up heat. The thin balloon allows the heat to pass through very quickly and warm the water. As the water closest to the flame heats up, it begins to rise and cooler water replaces it at the bottom of the balloon. This cooler water then soaks up more heat and the process repeats itself. In fact, the exchange of water happens so often that it keeps the balloon from ever popping! The soot on the bottom of the balloon is actually carbon. The carbon was deposited on the balloon by the flame, and the balloon remains undamaged. 5 mins See more at: http://www.stevespanglerscience.com/lab/experiments/firewaterballoon#sthas h.Vr7uLrTo.dpuf Why does the balloon with no water break in the flame? The flame heats whatever is placed in it. It heats the rubber of both balloons. The rubber of the balloon without water becomes so hot, that it becomes too weak to resist the pressure of the air inside the balloon. How does the balloon with water in it resist breaking in the flame? When water inside the balloon is placed in the flame, the water absorbs most of the heat from the flame. Then, the rubber of the balloon does not become very hot. Because the rubber does not become hot, it does not weaken, and the balloon does not break. Water is a particularly good absorber of heat. It takes a lot of heat to change the temperature of water. It takes ten times as much heat to raise the temperature of 1 gram of water by 1C than it does to raise the temperature of 1 gram of iron by the same amount. This is why it takes so long to bring a teakettle of water to the boil. On the other hand, when water cools, it releases a great deal of heat. This is why areas near oceans or other large bodies of water do not get as cold in winter as areas at the same latitude further inland. http://scifun.chem.wisc.edu/homeexpts/FIREBALLOON.html
Questions Describe the effects of heating and cooling on the volume of different materials, Identify applications of heating and cooling. In what ways can this be applied to the world around you? Hot air balloons use heat to expand the gases in the balloon, and because hot air rises so does the balloon and basket. Yet, to prevent what happened today, there is an opening at the top and bottom of the balloon. Firefighters use water to reduce heat. Your body even uses water to control heat. When you exercise, what’s that dripping from your armpits? EWWW... it’s sweat! But your body actually uses the water in your sweat to control your internal temperature so you don’t get overheated. Discuss examples of using the theory of thermal conduction in practical examples seen in the world around you and explore heat related technologies. radiator in cars pot on a stove Conclusion: Exit Pass: Clear as Mud? windshield exit pass. Draw how you felt about this class. If you feel confused about this concept draw a lot of bugs, if you feel like you understand your windshield will be clear. Explain why. Sponge: Play “Wink Murder” or “Who Started the Motion.”
5 mins