Unit 10: Energy

PSc.2.1.2

• Develop a conceptual cause-and-effect model for the phase change process that shows the relationship among particle attraction, particle motion, and gain or loss of heat - when a solid melts it has absorbed heat that increased the potential energy of its particles (space between particles) thus reducing the attraction between particles so that they can flow in a liquid phase. (Consider conditions of normal atmospheric pressure as well as the qualitative effects of changes in pressure involving gases.)
• The focus should be on the following phase changes: solid to liquid (melting), liquid to gas (vaporization), gas to liquid (condensation), and liquid to solid (freezing).
• Compare the process of evaporation to vaporization – materials that evaporate versus those which do not; attraction between surface particles and colliding air molecules.

PSc.3.1.1

• Infer the ability of various materials to absorb or release thermal energy in order to conceptually relate mass, specific heat capacity, and temperature of materials to the amount of heat transferred. (Calculations with q = mCp ∆T should be used to aid in conceptual development through laboratory investigation and analysis.)
• Compare thermal energy, heat, and temperature.
• Relate phase changes to latent heat that changes the potential energy of particles while the average kinetic energy of particles (temperature) remains the same. (Link to PSc.2.1.2)
• Compare conduction, convection, and radiation as methods of energy transfer.