Unit 2- Energy & States of Matter Part 1
Key Ideas and Learning Targets
1. Recognize that the model of matter that we use during this unit is essentially that proposed by Democritus.
2. Relate observations of diffusion to particle motion and collision in both liquid and gas phases.
3. Relate observations regarding the addition of energy by warming to increased particle motion.
4. Explain, at the particle level, how a thermometer measures the temperature of the system.
5. Explain the basis for the Celsius temperature scale.
6. State the basic tenets of Kinetic Molecular Theory (KMT) as they relate to gases:
Particles of a gas:
a. are in constant motion, moving in straight lines until they collide with another particle or a wall of the container in which they are enclosed.
b. experience elastic collisions; i.e., they do not eventually “run down”.
c. do not stick to other particles.
The speed of the particles is related to their temperature.
The pressure of a gas is related to the frequency and impact of the collisions of the gas particles with the sides of the container in which they are enclosed.
7. The 3 variables P, V and T are interrelated. Any factor that affects the number of collisions has an effect on the pressure. You should be able to:
· Predict the effect of changing P, V or T on any of the other variables.
· P is proportional to 1/V
P is proportional to T
V is proportional to T
· Explain (in terms of the collisions of particles) why the change has the effect you predicted.
8. Explain the basis for the Kelvin scale. Keep in mind that one must use the absolute temperature scale to solve gas problems.
9. Use factors to calculate the new P, V or T. Make a decision as to how the change affects the variable you are looking for.
PhET Simulation on Gas Properties
Evernote Notebooks and Storyboards
Click below to view notebooks for Unit 2 discussions: (entire notebook)
Diffusion Demonstration (cologne in air)
Cologne Diffusion Storyboard
Hot and Cold Water diffusion Storyboard
Manometers and barometers
States of matter summary notes, includes thermometer basics
Videos viewed during class
For the 3 videos below take notes that will provide a clear mental picture of how the three phases of matter would differ at the particle level in order to explain differences in properties of each phase.
Eureka- Molecules in Solids
Eureka- Molecules in Liquids
Eureka- Evaporation and Condensation (focus on behavior of gas particles, not on the actual process of evaporation and condensation)
For the two videos below, focus your notes on how a thermometer works and is calibrated and also on the development of the Fahrenheit and Celsius scales.
Eureka! Expansion and Contraction (optional)
Thermal Expansion (think about what the increase or decrease in temperature does to the motion of the particles)
Eureka- Measuring Temperature(how does a thermometer work? Now that you know how liquids expand/contract, how does this idea lead you to understanding how a thermometer works?)
Mr. Wizard- The Science of Straws (I loved watching this show while I was growing up. A great demonstration of pressure)