# Connected Chemistry Unit 1: Gas Laws

**Subject:** Chemistry

**Time:** 8 classes, 45-50 min each

**Level:**

Introductory High School Chemistry

## Unit Overview

This is an 8 day unit designed to cover high-school level topics in the properties of gases and gas particle behavior while engaging students in computational thinking practices. The lessons use computer models to explore these topics in greater depth and using a greater degree of student inquiry and guided discovery than would be typically possible through other learning activities in the same amount of time. Throughout the unit, students will learn the rules that govern gas behaviors and interactions by adding the rules into the model one-by-one. The computer models enable students to investigate what causes pressure in a gas, how it is measured, and how it is affected by the properties of the particles that make the gas and the characteristics of the container they are in (ideal gas law).

In **Lesson 1**, students first focus on three real-life examples of systems involving gases - a bike tire, a syringe, and a soda can. Then they look at a simple model of the bike tire, observing the particles that make up the gas inside the bike tire. Students explore the model by changing parameters in the interface, gaining a familiarity with a microscopic view of the system and with the NetLogo model interface they will use again in later lessons. Finally, students are introduced to the code behind the model and have an opportunity to modify the code.

In **Lesson 2**, students are introduced to the scientific concepts of the Kinetic Molecular Theory, pressure, and ideal gases. They are given a definition of pressure and then guided through an investigation of how particles create pressure at the microscopic level. Students observe the effects that adding particles through a valve in the tire has on the pressure of the tire. Students consider the trade-offs of making simplifications when constructing models of systems. They are then introduced to sub-procedures in code and use this tool to to examine what determines the kinetic energy of the simulated particles.

In **Lesson 3**, after using Command Center to collect data, students are introduced to a new tool called BehaviorSpace, which automates data collection in the model. They use BehaviorSpace and Excel/Google Sheets to investigate the quantitative relationship between the number of particles in a container and the pressure inside. In Excel/Google Sheets, the students sort and clean their data, then create a graph and find a trendline. Students use the trendline equation to predict and test their prediction for new pressure values.

In **Lesson 4**, students connect all their previous gas particle investigations. Accordingly, the model used in this lessons combines the features from previous lessons. Students explore different ways to change parameters and produce the same pressure. They then use the Ideal Gas Law to predict pressure values for different variable combinations and test their predictions using the model. Finally, students return to the code to explore the thought process of constructing this model.

## Lessons Overview

Students first focus on two real-life examples of systems involving gases - a bike tire and a syringe. Then they look at a simple model of the bike tire, observing the particles that make up the gas inside the bike tire. They then learn the rules that govern their behaviors and interactions by adding the rules into the model one-by-one. While observing the consequences of “running” these rules and the resulting motion of the particles. In this model students gain a familiarity with a microscopic view of the system and with the NetLogo model interface they will use again in later lessons. This familiarity is a critical learning goal in the first lesson, since the use of computer interface (buttons, sliders, switches, etc…) becomes progressively more sophisticated in future activities. Finally, students are introduced to the code behind the model and have an opportunity to modify the code.

Students are introduced to the scientific concepts of the Kinetic Molecular Theory, pressure, and ideal gases. They are given a definition of pressure and then guided through an investigation of how particles create pressure at the microscopic level. Students observe the effects that adding particles through a valve in the tire has on the pressure of the tire. Students consider the trade-offs of making simplifications when constructing models of systems. They are then introduced to sub-procedures in code and use this tool to to examine what determines the kinetic energy of the simulated particles.

After using Command Center to collect data, students are introduced to a new tool called BehaviorSpace, which automates data collection in the model. They use BehaviorSpace and Excel/Google Sheets to investigate the quantitative relationship between the number of particles in a container and the pressure inside. In Excel/Google Sheets, the students sort and clean their data, then create a graph and find a trendline. Students use the trendline equation to predict and test their prediction for new pressure values.

In this Lesson, students connect all their previous gas particle investigations. Accordingly, the model used in this lessons combines the features from previous lessons. Students explore different ways to change parameters and produce the same pressure. They then use the Ideal Gas Law to predict pressure values for different variable combinations and test their predictions using the model. Finally, students return to the code to explore the thought process of constructing this model.

## Compatible With

mac

windows

laptops

chrome books

phones

tablets

## What's Next?

## Standards

**Next Generation Science Standards**

- NGSS Crosscutting Concept
- Systems
- NGSS Practice
- Asking Questions, Defining Problems
- Using Models
- Conducting Investigations
- Analyzing Data
- Arguing from Evidence

**Computational Thinking in STEM**

- Modeling and Simulation Practices
- Assessing Computational Models
- Designing Computational Models
- Using Computational Models to Find and Test Solutions
- Using Computational Models to Understand a Concept
- Computational Problem Solving Practices
- Assessing Different Approaches/Solutions to a Problem
- Computer Programming
- Troubleshooting and Debugging
- Data Practices
- Analyzing Data
- Collecting Data
- Creating Data
- Manipulating Data
- Visualizing Data
- Systems Thinking Practices
- Investigating a Complex System as a Whole
- Thinking in Levels
- Understanding the Relationships within a System

## Acknowledgement

This work was made possible through generous support from the National Science Foundation (grant 0115699).

## Comments, Feedback, and Questions