Station 1: Temperature

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2 Station 1: Temperature Temperature is the measure of kinetic energy of the particles in a substance. The movement of particles is actually what we measure as temperature. As we heat up substances, the particles move at faster speeds which causes them to bump into each other more and spread apart. At lower temperatures, the particles are slower and closer together.

3 Station 2: Thermal Energy Thermal Energy is the TOTAL energy (kinetic and potential) of ALL particles in a substance. This means that a colder substance can actually have more Thermal Energy than a hotter substance so long as you have more particles. This is easy to imagine if you picture two computer factories of the same size: In the first, you have 5 workers that can each make 10 computers in one day. In the second, you have 40 workers that can each make 5 computers a day. Lower Temperature More Particles Higher Thermal Energy Higher Temperature Less Particles Higher Thermal Energy Even though the first factory has faster workers (higher temperature), the second factory has more workers (more particles) so it can make more computers per day (has a higher thermal energy).

4 Station 3: Heat Heat is the transfer of energy from an area of high temperature to an area of low temperature. This is where the famous phrase comes from, Get out of the kitchen, if you can t take the transfer of energy from an area of high temperature to an area of low temperature. Heat travels the same way that a concentration gradient goes, from HIGH to LOW. Heat can be transferred in 3 different ways: Radiation, Conduction and Convection When you touch cold hands to a warm mug, there is a high concentration of heat in the mug and low concentration of heat in your hands. The energy then transfers from the warm mug to your hands and you can be happy again. When you cook an egg, the energy travels from the high heat concentration in the burner to the low heat concentration in the egg.

5 Station 4: Radiation Radiation is the transfer of heat by electromagnetic waves that travel through air and space Heat is able to transfer by radiation without touching the object it is warming up. This is how the Sun warms the Earth, a microwave warms your food, and a fireplace warms your hands. Heat Radiation is sometimes referred to as Infrared Radiation

6 Station 5: Conduction Conduction is the transfer of heat between two objects that are touching. Materials that are good conductors like metals are able to transfer heat faster than poor conductors like wood. This is how you burn your hands on scalding hot water, stovetops, and curling irons! This is because the particles in good conductors are able to move more freely, so they can bump into each other easily and pass energy along.

7 Convection is the transfer of heat in liquids and gases. Station 6: Convection Hot water near the bottom will rise and then cool as it rises causing it to fall. This creates circular patterns of movement called convection currents Convection and convection currents occur in air around the Earth due to heating by the Sun. They also occur in the magma in the Earth s Mantle that is underneath the Earth s crust Convection is what causes lava in lava lamps to rise as they heat up and fall as they cool.

8 Station 7: Phase Changes A phase change is when a substance changes from a one form of matter (solid, liquid or gas) to another. As heat is added to substances, it causes the particles to move faster and bump into each other more. This causes the particles to spread out which will result in phase changes. Each type of phase change has its own name. For example, when a substance goes from a solid to a liquid it is called melting as we all know. Each phase change occurs at certain temperatures for different materials. These are called the melting point, freezing point, boiling point, and condensation point.

9 Station 8: Heating Curve of Water As you heat an ice cube, at certain temperatures it will change phases to a liquid and then a gas. This occurs in steps as shown in the graph below. As you heat up ice, the temperature will increase until it begins to melt around 32ᵒF. The ice will actually remain at this temperature until it completely melts, and then the temperature will start to rise again. A similar stall in the temperature will happen when the liquid water starts to evaporate/boil off around 212ᵒF Once it is completely boiled off, the temperature will begin to rise again. The same phenomenon occurs when you are cooling a sample.

10 Station 9: Nuclear Fission and Fusion Nuclear Fission is the splitting of an atom into smaller atoms Nuclear Fusion is the combining of multiple small atoms into a larger atom. Nuclear FUSION is what occurs on the Sun! Many Hydrogen Atoms combine to form Helium Atoms

11 Station 10: Exothermic and Endothermic Reactions Exothermic reactions are chemical reactions that release energy -Ex) an atomic bomb involves splitting an atom s nucleus which causes a large release of energy Endothermic reactions are chemical reactions that absorb energy -Ex) when a phosphate group is attached to ATP, it absorbs energy which is stored for later use

12 Videos Heat Transfer: 8 Heating Curve of Water: Heating Curve Time Lapse:

13 Review What is happening during the flat sections on the heating curve of water? Phase Change! Energy is breaking bonds instead of heating water

14 Review What is the process that allows hot air balloons to rise? Convection!

15 Review What is the difference between nuclear fusion and fission? Nuclear Fusion is smaller atoms combining Nuclear Fission is larger atoms breaking apart

16 Review What process does the Sun use to generate heat? Nuclear Fusion!