Icy Hot Lab

 Wear your safety goggles at all times!
 Keep loose clothing and hair back and away from the Bunsen burner flame.
 The beakers will get hot! Use the beaker tongs to remove the beaker and dispose of boiling water in the sink.

 Sketch a diagram illustrating the particles of solid water (ice), liquid water, and water vapor (gas).
 Describe the shape, volume, and mass of water as it changes from one phase (state) to the next. For example: Solid water has a constant shape – meaning the cubes of ice hold their shape when dumped onto the table.

 Pick up a copy of the Energy and Kinetic
Theory of Matter Reading.
 Read page 1. In your chemistry journal, list the three guiding principles used to understand energy.
 Read page 2. Use a graphic organizer to compare / contrast money and energy.


What are the three energy “accounts” used to explain changes in substances or their arrangements in chemistry.
 What are the three ways to transfer energy into or out of a substance?

 Energy can be transferred from one
“account” to another during chemical or physical processes.
 Total energy (like mass) before the change equals the total energy (mass) after the change as long as no energy (mass) enters or leaves the system.

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 If energy is transferred into or out of the system, the change in energy equals the energy transferred by heating, working, or radiating.
ΔE = Q + W + R

 Matter is made up of tiny particles that are in constant motion.
 Kinetic Theory of Matter Simulation

 These particles exert long range attractions and short range repulsions on each other. Attractions reduce the interaction energy (E i
) while repulsions increase interaction energy.
 Phase Change Simulation

 A warmer sample has (on average) faster moving particles than a cooler sample.

Energy Transferred (Heat)

Discussion Questions: Chemical or
Physical Change?
 Was the observed phase changes a chemical change of a physical change?
How do you know?

Discussion Questions: Endothermic or Exothermic Change?


Endothermic change – Change caused by the transfer of energy (heat) into a substance.
Exothermic change – Change caused by the transfer of energy (heat) out of a substance.
 Where the phase changes you observed in the lab exothermic or endothermic?

Discussion Questions: Kinetic
Energy or Interaction Energy?
 Was the energy transferred to the substance stored as kinetic energy? How can you tell from the Temperature vs. Time graph?
 Was the energy transferred to the substance stored as interaction energy?
How can you tell from the Temperature vs.
Time graph?

Discussion Questions: Heating
Slowly or quickly?
 How would the Temperature vs. Time graph change if we used two bunsen burners instead of one?