Exploratorium

=**__EXPLORATORIUM: THERMAL ENERGY__**= BY: ALLISON IRWIN ASSISTANTS: LINDSAY MARELLA & SARAH GORDON

__DEMONSTRATIONS__ 1. Ice Melting Blocks 2. Make a Thermometer: http://www.energyquest.ca.gov/projects/thermometer.html 3.Soda Can Crush (Source: www.msu.edu/~santalam/chemistry/.../gas%20law%20demos.doc) 4. Balloon Demo: http://www.sciencekids.co.nz/experiments/heavyair.html



__GIVE AWAYS__ 1. Thermometer from Demo 2 2. PTV Popsicle Stick (Source: www.msu.edu/~santalam/chemistry/.../gas%20law%20demos.doc) __MATERIALS__ 1. Ice Melting Blocks -ice -blocks 2. Thermometer - bottle (need 1 per student) -clear straw -rubbing alcohol -food coloring -clay 3. Soda Can Crush - can (need at least 1 per demonstration) -water -beaker of ice water -hotplate 4. Hot Air Balloon -balloon -bottle -pot of water -hotplate 5. PTV Sticks - large popsicle sticks / tongue depressors

__SCRIPT: UPDATED 5/31/12__

Much improved!

Hi everyone, welcome to the Exploratorium! I'm Allison and these are my assistants Lindsay and Sarah. Feel free to ask us any questions that you have. We're going to teach you about thermal energy today. Thermal energy is another word for heat. Does anyone know what heat is? "Heat is the warmth of an object." All objects have thermal energy.

1. Our first demonstration is the **Ice Melting Blocks**: 2. Now we are going to make a Thermometer 3. Now we are going to crush a can using only thermal energy! 4. Balloon Demo:
 * This will show you how heat is transferred from one object to another.
 * We already said that heat is the warmth of an object.
 * Heat will move from one place to another because there is a difference in temperature. Temperature is how much heat an object has.
 * Heat will naturally flow from places with high temperature to places with low temperature (2nd Law of Thermodynamics) (A cold object can't heat up a warm object.
 * Heat can transfer (move from one object to another) through conduction. Conduction is when two objects touch.
 * How much heat is transferred between two objects depends on how much of each object there is and the temperature of each object. For example, a big object will give off more heat than a small object of the same material.
 * How much heat is transferred also depends on the object's specific heat capacity. The specific heat capacity is the amount of heat needed to raise the temperature of an object by one degree Celsius. Every material has its own constant of specific heat.
 * A high specific heat means that it does not transfer heat easily (foam).
 * A low specific heat means that it transfers heat very easily (aluminum). (//Ask students to put the arrows next to the numbers on the chart of specific heat values).//
 * Now that you know what specific heat capacity is, we are going to have a race. Each of you will get one of these blocks. Some of the blocks are made out of aluminum and some of them are made out of foam. We are going to put ice cubes on the blocks.
 * Because the two blocks have more heat (they are warmer) than the ice cubes, the blocks will transfer heat to the ice.
 * "What happens when ice becomes warmer?" --> "It melts."
 * The block with the lower specific heat capacity will transfer the heat quickly. The block with the higher specific heat capacity will transfer the heat slowly.
 * "Which block will melt the ice quicker?" --> "The aluminum one."
 * //Perform demo//
 * The aluminum block melted the ice cube quicker because it has a low specific heat capacity. The heat from the warm aluminum block transferred to the cold ice cube through conduction.
 * The foam block melted the ice cube slowly because it has a high specific heat capacity. The heat from the warm foam block transferred to the cold ice cube through conduction.
 * We already said that temperature is the amount of heat in an object.
 * Thermometers measure temperature (therm means heat, ometer means measuring device)
 * There are 3 different scales for measuring temperature. In America we use Fahrenheit, in Europe they use Celsius, and a lot of time in science we use Kelvins. All of the scales measure the heat of objects. //Show poster with freezing points & boiling points.//
 * The way a thermometer works is that when the fluid becomes hotter, it takes up more space. (Its volume increases) When the fluid becomes colder, it takes up less space. So when it is really hot outside the liquid inside the thermometer goes up the tube. When it is really cold outside the liquid inside the tube goes down.
 * Sometimes we use mercury in the thermometers in physics class, but mercury is dangerous so most of the thermometers today have alcohol in them instead.
 * Now we are going to make out own thermometers. We are going to use a mix of water and alcohol.
 * You can pour the cups of water and rubbing alcohol into your water bottle now. Be careful not to spill, we will help you use the funnels.
 * Now you get to drop some food coloring in so you can see the liquid better.
 * Now you are going to take a piece of model magic and mold it around the straw. Now put the straw into the bottle and plug the hole. Make sure that the straw does not touch the bottom of the bottle.
 * Now you draw a line at the water level. This line marks room temperature.
 * When you go home, if you stick this in the freezer and let the mix freeze, you can make another line to mark the freezing point. Where will this line be? Above or below the room temperature line? "Below."
 * Then you can leave it outside in the hot sun. Where will the water line be? "Above the room temperature line."
 * A gas’s __**pressure**__ is the force it puts on the objects around it.
 * When the temperature of a gas goes **up**, it puts **more** force on the objects around it.
 * When the temperature of a gas goes **down**, it puts **less** force on the objects around it.
 * You can use these popsicle sticks to help you remember.
 * Everyone hold the letter V with there thumb and pointer finger. You hold the V because the volume (how big the can is) stays the same.
 * If temperature goes up, push up on the bottom of the T and see that the P also goes up.
 * So, now for the demo. Boiling the water in the can increases temperature inside the can so the pressure inside the can also increases.
 * The temperature inside the can is higher than the temperature outside the can.
 * The pressure of the air inside the can is higher than the pressure of the air outside the can.
 * Suddenly putting the can in the ice water decreases temperature, and the sudden decrease in pressure on the inside of the can causes the walls of the can to be pushed inwards because the pressure on the outside of the can is greater than the pressure on the inside of the can (it reaches equilibrium)
 * A gas’s __**volume**__ is the amount of space it takes up.
 * When the temperature of a gas goes **up**, it takes up **more** space.
 * When the temperature of a gas goes **down**, it takes up **less** space.
 * You can use the popsicle sticks to help you remember.
 * Everyone hold the letter P with there thumb and pointer finger. You hold the P because the pressure (this is the force of the air on the balloon) stays the same.
 * If temperature goes up, push up on the bottom of the T and see that the V also goes up.
 * The temperature of the air inside the balloon goes up.
 * The volume of the balloon increases (it inflates).

If there is extra time remaining, the kids will decorate their thermometers using stickers.

POSTER: UPDATED 5/29/12 FINAL POSTER: