MOLECULES AND MINDS:Optimizing Simulations for Chemistry Education

Introduction

The following lesson plans are resource materials designed to provide teachers with a plan of action for integrating the Molecules and Minds chemistry simulations into their curriculum. All of the simulations model chemistry concepts that are informed by the kinetic molecular theory (KMT). The plan of action sequence is as follows:

1.Pre-test

2.Kinetic theory simulation lesson plan

3.Kinetic theory demonstration lesson plan

4.Diffusion simulation lesson plan

5.Diffusion demonstration lesson plan

6.Gas Laws simulation lesson plan

7.Gas Laws demonstration lesson plan

8.Phase change simulation lesson plan

9.Phase change laboratory activity plan

10.Post-test

This packet contains Steps 2 - 9 in the sequence. This resource material is a guide for teacher use and teachers should feel free to exercise their professional judgment when deciding which aspects of these lessons they will integrate into their own lessons.

All the lesson plans in this sequence were originally developed by Max von Euw, a chemistry teacher at the School for Democracy and Leadership in New York City. We thank him for his thoughtful pedagogical analysis of the simulations.

Suggested Sequence:

Pretest/Surveys / Day 1
Intro to the study
Kinetic theory simulation / Day 2
Kinetic theory
demo/lab / Day 3
Diffusion simulation / Day 5
Diffusion demo/lab
Day 5
Gas Laws simulation / Day 6
Gas Laws
demo/lab / Day 7
Phase change
simulation / Day 8
Phase change demo/lab / Posttest

experimental

KINETIC THEORY:Simulation worksheet

Name: ______Date: ______Class: ______

The Kinetic Theory Worksheet

Instructions: As you go through the simulation, please answer the following questions. This is individual work unless I say otherwise! All the answers are in the text and vocabulary list, so read everything carefully! This is to be finished by the end of class…it can be done!

Vocabulary list:

Theory: an accepted statement about science that has been tested and peer reviewed many times and can be used to make predictions.

Kinetic: this word means movement. Kinetic energy is energy that

has to do with things moving.

To examine: means to look at or study.

Rigid: Solid, difficult to bend, not flexible.

Pressure: The amount of force per area. If you are pushing

against a wall, you are putting pressure on the wall.

Internal Pressure: The amount of pressure inside a container.

Gas molecules can push against the walls of a container.

External Pressure: The amount of pressure put on the outside of a container. If you sit on a box, you put pressure on the box.

Particles: All matter is made up of tiny particles. Think of them as tiny, round, hard balls.

Variable: Something that varies or changes.

Atmosphere: This is a unit of pressure represented by ‘atm’.

Kelvin: This is a unit of temperature that scientist use represented by ‘K’. 298 K is about room temperature (= 25 degrees C).

Questions to do BEFORE you mess with the simulation!!

Screen 1 (5 min)

  1. Who is the main character? ______
  2. What is her issue or problem? ______

______

  1. What does ‘kinetic’ mean? ______

______

  1. Give a real life example of a gas that is affected by the kinetic theory? ______
  2. Do variables change or remain constant? ______
  3. List 2 variables that affect gas particle motion:

______

  1. What are the 2 aims for this simulation?

Aim1:______

Aim2:______

Screen 2 (5 min)

8. What are the units of each property we are studying?

Property / Unit

9.List two ways that you can change the temperature on the computer program

______

Screen 3: The simulation (20 min)

Things to do for the GRAPHING portion of the worksheet

You need to graph at least 12 points for each graph, I’m going to start you off but you need to complete the rest!

Graph 1: lock the temperature at any temp you want. T = ______K

Number of Particles / Internal Pressure (atmospheres)
10
11
12
13
14

Before you go on, please copy the graph you made onto this worksheet.

Graph 2: lock the number of particles at any number you want. Number of particles = ______particles.

Temperature (Kelvin) / Internal Pressure (atmospheres)
300
325
350
400
475

Before you go on, please copy the graph you made onto this worksheet.

Graph summaries (circle the words in parentheses)

Graph 1: As I increased the number of particles, the internal pressure ______.

This means the gas molecules pushed (harder / softer) against the walls of the container. When I put more molecules into the container, they want to escape (more / less).

Graph 2: As I increased the temperature, the internal pressure ______.

This means the gas molecules pushed (harder / softer) against the walls of the container. When I put more molecules into the container, they want to escape (more / less).

Please hit ‘DONE’ on the simulation, then fill out a quick survey and hit ‘SUBMIT’…you are almost finished!

The last part…bringing it all together

Screen 4 (10 min)

OH, USE COMPLETE SENTENCES THIS TIME…

  1. How is the smell of the bathroom at Gabriella’s school or the scent of air freshener like the moving particles in the program? ______
  2. How is the bathroom like and not like the container in the program?

Like:______Not Like: ______

3. Based on the kinetic theory, would Gabriella smell the bathroom faster than the first time described in the program if the temperature was higher? ______

Why or why not? ______

______

NOW HIT ‘DONE” AND YOU ARE…DONE! Thanks!

If you still have time (a little added bonus):

Log back into the program and set a particle number and temperature. Then click on the ‘Trail’ and ‘Color’ button. Watch the one particle.

Does it move in a specific pattern? ______

Would you say the gas particle has a random motion? ______

If you increase the temperature, does that particle move faster or slower? ______

Homework: Conversions

200 hm = ______m5000 mm = ______dm100 cm = ______km

5.5 g = ______mg200 kg = ______g50 mg = ______g

km / hm / dam / m / dm / cm / mm
kg / hg / dag / g / dg / cg / mg

experimental

KINETIC THEORY:Demo/Lab

Day 2 Lesson Plan: Kinetic Molecular Theory

Aim: What is the Kinetic Theory and how do we know the simulation was true?

Agenda:

  • Do Now – 7 min
  • Thoughts on the Simulation – 5 min
  • Gases – KMT – lecture/notes – 15 min
  • What is pressure? – 10 min
  • Demos – balloon and temp / can and water – 10 minutes
  • What’s next??? (diffusion) – 5 minutes

Simulation feedback…what was the most confusing thing? What worked…any improvements I can make on the handout?

Kinetic Molecular Theory: Describes the behavior of gases.

The variables involved are pressure, volume, temperature, and # of particles, size of particles.

Gases contain particles that are in straight, random motion

Gases particles collide with each other and the wall…these collisions are elastic (not like a tennis ball)

Gas particles are spread out, so they don’t take up space.

Gas particles are not attracted to each other

Demonstration: Balloon and flask on hot plate

What is pressure?

Pressure is the amount of force applied over a surface.

To apply pressure on a wound; to apply pressure on a wall; water pressure;

Gas molecules can apply pressure on the walls of a container.

Shake up a coke bottle…the bottle becomes harder because you’ve increased the pressure inside the bottle. How?

Internal vs. External Pressure

Pressure is measured in atmospheres (atm)

The simulation…As you increased the temperature, the pressure went up.

As you increased the number of particles, the pressure went up.

If the pressure of the gas increases, would it push harder or softer against the walls.

Balloon  increase temperature, # of particles is locked (or constant), what happens to the pressure inside the balloon?

What keeps the bottle’s shape? Why does an empty bottle not completely crumple up?

Diffusion has to do with injecting a gas into a container and seeing how long it takes to spread out.

Name: ______Date: ______Class: ______

Do Now: Kinetic Theory

What did you think about the simulation? ______

Why? ______

______

Other than any technical difficulties, what are some improvements that could be made?

______

When you increased the temperature, what happened to the pressure? ______

When you increased the number of particles, what happened to the pressure? ______

When there is more pressure inside the container, do you think the gas particles wanted to escape more or less from the container? ______

When you increased the temperature, did the particles move faster or slower? ______

When the particles were moving did you think they were moving in a pattern or a random motion? ______

If you didn’t do the simulation (didn’t get past the first 10 questions in the handout), please explain to me why you didn’t get that far…for full credit on the Do Now you need to write at least five complete sentences. Can you answer the questions above? Do you feel lost in this class? What do you need to do to catch up? (answer on the back of the page)

Image of Balloon Demonstration Set-up

experimental

DIFFUSION:Simulation worksheet

Name: ______Date: ______Class: ______

Diffusion worksheet

Vocabulary list:

Helium: A type of gas. It is a very light gas and when you inhale it, your voice changes pitch.

Argon: A type of gas. It is a heavy gas.

Neon: A type of gas. It is heavier than helium, but lighter than argon.

amu: This stands for atomic mass unit. It is the unit for the mass of atoms.

Screen 1 (5 min)

  1. Who is Gabriella’s brother? ______
  2. How did Gabriella know that he was making a snack? ______
  3. What 2 variables affect diffusion? ______and ______
  4. What are we trying to figure out by using this program? ______

Screen 2 (5 min)

  1. What are the units for temperature? (What do we measure temperature in?) ______
  2. What is atomic mass measured in? (What are the units of atomic mass)? ______
  3. What are the 2 gases we are injecting into the chamber? ______and ______
  4. Which gas is heavier? ______
  5. How do you inject atoms (particles) into the chamber? (What button do you have to click?) ______

Screen 3: The computer simulation (20 min)

What color are:

the helium particles? ______the argon particles? ______the neon particles? ______

To figure out how the temperature affects diffusion, please fill out the following tables:

Gas: Helium or Argon (circle the one you have chosen to test )

Temperature (K) / Time 1 (s) / Time 2 (s) / Time 3 (s) / Average Time (s)
350
550

Before you go on, please copy the graph from the computer program onto this worksheet.

Please repeat the process for the other gas:

Gas: Helium or Argon (circle one)

Temperature (K) / Time 1 (s) / Time 2 (s) / Time 3 (s) / Average Time (s)
350
550

Before you go on, please copy the graph from the computer program onto this worksheet.

To figure out how the mass affects diffusion, please complete the following graph by plotting the averages you calculated for Helium and Argon.

Use 2 different

symbols for the

helium and for

the argon gas.

You should have 2

dots for each

Temperature.

Argon

Helium

When you have finished graphing, please hit ‘DONE’ on the simulation,

then fill out a quick survey and hit ‘SUBMIT’…you are almost finished!

Bringing it all together

Screen 4 (10 min)

  1. How is the popcorn odor Gabriella could smell as she entered the apartment like the atoms you injected into the container in the program? ______
  2. How is Gabriella’s apartment like the container in the program? ______
  3. How is the air in the apartment like the neon gas in the program? ______

Please hit ‘DONE’…thank you

Diffusion summary(5 min)

Circle one of the words in parentheses:

  1. As the temperature increased, it took the molecules (less / more) time to reach the detector.
  2. As the temperature increased, the gas particles moved (faster / slower).
  3. As the mass of the gas increased, it took the molecules (less / more) time to reach the detector.
  4. As the mass of the gas increased, the gas particles moved (faster / slower).
  5. Why do you think we took 3 measurements for each gas and then used the average? Why weren’t the times always the same if the settings (temperature and type of gas) were the same? (We learned this yesterday…it has to do with the KMT). ______

experimental

DIFFUSION:Demo/Lab

Day 4 Lesson Plan: Diffusion

Aim: What is diffusion and what are some of the conditions where we can observe it?

Agenda:

  • Do Now –10 min
  • Diffusion: Definition, lecture/notes – 15 minutes
  • Connection to the simulation, calculation – 15 minutes
  • Demo: Diffusion of food coloring in hot and cold water – 10 minutes
  • Homework: Write me a story/comic

Diffusion: describes how one gas or liquid spreads through another gas or liquid.

It depends on the mass (or size) of the particles and the temperature.

If the particles are small, they travel fast. If the particles are big, they travel slowly.

If the temperature is hot, they travel fast. If the temperature is cold, they travel slowly

Question:How is the diffusion we studied similar and different from the diffusion we learned in living environment (biology)?

Similar: traveling through another solution

Different: Energy requirements

Simulation Question:

How come each gas didn’t always take the same amount of time to reach the detector?

Calculation: Graham’s law of diffusion

The heavier the particle, the slower it traveled

Graham worked out that the rate at which the particles spread out is inversely proportional to the square root of the molecular weight. We can write his law as a mathematical equation that should "fit" with the results you got from the simulation:

RateHe/RateAr = √39 (mass of Argon)/√4 (mass of Helium)

So what might we predict about the rate of Argon when compared with the rate of Helium? How do the results you recorded from the simulation compare with your prediction? Students can check their results.

How do we know the simulation is true? One way we can do it is the way we did in 3 – seeing whether it can be used to make a prediction. But we can also see how it works with our experiences in our lives.

You see diffusion everyday but perhaps not in the same form as the gases you studied in the simulation. We can describe a gas as a fluid. Are there any other fluids you use that also show diffusion?

Student feedback about where they might observe diffusion e.g. tea, coffee, cocoa, sugar

Demonstration/Student Activity: Diffusion in liquid (another fluid) and the effect of temperature

  1. Heat beaker of water on hotplate
  1. Also get the same amount of cold water in another beaker of the same size
  1. Have a couple of student volunteers (one for hot and one for cold) with stopwatches to record the rate of diffusion
  1. Have a couple of students (one for the hot water and one for the cold) add one drop of food coloring
  1. The student recorders should record how long it takes for the food coloring to diffuse throughout the water. (When this was done the first time the hot beaker was left on the hot plate and was boiling and one of the students suggested that it was the boiling which was helping the color to diffuse in the hot water. So then I took a second beaker of boiling water off the hot plate and repeated the test in hot water that was still rather than moving[A teachable moment!])
  1. Discussion about gases and liquids and diffusion and the effect of temperature and mass on the rate (Would Gabriella and her friends be able to smell the bathroom more quickly on a hot summer's day than a cold winter's day?)
  1. So how good is that simulation!?

Name: ______Date: ______Class: ______

Do Now: Diffusion

What 3 gases did we mess with (use) in the diffusion simulation? ______

Which one was already in the container before you injected the other gas? ______

Which gas moved the fastest? ______

Why did that gas move faster than the others? ______

What is the definition of diffusion? ______

______

Do you have any feedback about the diffusion simulation? (you have to write something!)

______

Diagram of Diffusion Demonstration Set-up


Homework: Diffusion

Write me a story or a comic book

You are going to pretend that you are a gas particle that has been injected into a closed box. I want you to describe your thoughts as a particle inside this box. To complete this task you need the following terms:

Straight, random motion

Elastic collisions

Attraction toward other gas particles

Your speed compared to other particles

Your mass/size

What happens when the temperature increases.

Your story needs to be at least 1 page long; if you choose to do a comic book it needs to be 15-20 frames long!

experimental

GAS LAWS:Simulation worksheet

Name: ______Date: ______Class: ______

Gas Laws Worksheet (Charles’, Boyle’s, and The Combined)