Unit: Heat (Heat Temp, Heat Transfer)

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Unit: Heat and Thermal Energy

Central Concept-Energy: The term “heat” as used in everyday language refers both to thermal energy (the motion of atoms or molecules within a substance) and energy transfers by convection, conduction, and radiation (particularly infrared and light). In science, heat is used only for this second meaning; it refers to energy transferred when two objects or systems are at different temperatures. Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present.

Central Concept-Conservation of Energy and Energy Transfer:Heating is another process for transferring energy. Heat transfer occurs when two objects or systems are at different temperatures. Energy moves out of higher temperature objects and into lower temperature ones, cooling the former and heating the latter. This transfer happens in three different ways—by conduction within sol- ids, by the flow of liquid or gas (convection), and by radiation, which can travel across space. Even when a system is isolated (such as Earth in space), energy is continually being transferred into and out of it by radiation. The processes under- lying convection and conduction can be understood in terms of models of the possible motions of particles in matter. Radiation can be emitted or absorbed by matter. When matter absorbs light or infrared radiation, the energy of that radiation is transformed to thermal motion of particles in the matter.

Science and Engineering Practices-Analyzing and interpreting data: After data has been collected, it must be analyzed in order to derive meaning. This allows scientists and engineers to identify significant features and patterns in the data, which can lead to drawing conclusions and possible solutions.

Learning Objectives:

By the end of this unit, you should be able to.... (Those in bold will be essential & will be assessed formally in the curriculum)

1.	Distinguish between molecules, atoms, and the subatomic particles (proton, neutron, electron).
2.	Distinguish between temperature (average kinetic energy of particle), thermal energy (total internal energy), and heat (thermal energy in transit)
3.	Identify and use appropriate units for temperature and thermal energy. Describe the common temperature scales and memorize certain values.
4.	Explain that heat moves from regions of high temperature to regions of cold temperature and how this results in thermal equilibrium.
5.	Define and use the units of heat energy (calories and kilocalories), and relate these to other forms or energy, and to power.
6.	Identify and give examples of heat transfer: conduction, convection, radiation.
7.	Predict the phase of a material based on its temperature, and its melting and boiling point.
8.	Relate a temperature-time graph for a substance to the phase (solid, liquid, gas) of the substance and its boiling and melting points.
9.	Relate energy to changes of phase, using appropriate vocabulary for phase changes (melting, boiling, freezing, condensing, subliming).
10.	Make calculations relating the temperature change in a substance, the amount of heat transferred, the amount of substance, and the specific heat of the substance.
11.	Describe how water’s high specific heat capacity affects climate.

Vocabulary:

element	atom	electron	proton	neutron
molecule	nucleus	temperature	Celsius scale	Fahrenheit scale
Kelvin scale	absolute zero	heat	thermal contact	thermal equilibrium
internal energy	calorie	kilocalorie	Joues	specific heat capacity
conduction	convection	radiation	solid	liquid
gas	plasma	phase	state	latent heat of husion
latent heat of vaporization	phase changes	cooling curve	heating curve