Summary

In this activity, students will learn how to count atoms and how to balance chemical equations using a simulation and games from PhET Interactive Simulations.

Grade Level

Middle School, High School

NGSS Alignment

This simulation will help prepare your students to meet the performance expectations in the following standards:

• HS-PS1-2: Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.
• HS-PS1-7: Use mathematical representation to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.
• Scientific and Engineering Practices:
  • Developing and Using Models

Objectives

By the end of this activity, students should be able to:

• Balance a chemical equation.
• Understand that the number of atoms of each element is conserved in a chemical reaction.
• Recognize and explain the difference between coefficients and subscripts in a chemical equation.
• Translate between the written description of a chemical reaction and a symbolic representation.

Chemistry Topics

This activity supports students’ understanding of:

• Chemical reactions
• Balancing Equations
• Reactants
• Products
• Conservation of Matter
• Chemical formula
• Coefficients
• Subscripts

Time

Teacher Preparation: 10 minutes

Lesson: 45 minutes

Materials

• Computer, tablet, or Chromebook
• Student handout
• Balancing Chemical Equations Simulation

Safety

• No specific safety precautions need to be observed for this activity.

Teacher Notes

• It is suggested that students work individually, and at their own pace through this activity. Instructions for working through the simulation are included on the student activity sheet.
• The accompanying activity also includes a “PhET Tips for Teachers” download with suggestion for using the simulation.
• See the student document below for background information, vocabulary, rules for balancing chemical equations, and sample problems.
  
• Here are some online videos that may help students balance chemical equations:
  • Introduction to Balancing Equations
  • Balancing Chemical Equations
  • Balancing Chemical Equations 2
  • Balancing Chemical Equations 3
  • Balancing Chemical Equations

• Here are some alternate balancing chemical equations simulations and games suggestions:
  • GCSE Balancing equations quiz – rags to riches
  • Balancing Equations (the format is similar to the previous game but the questions are different)
  • GCSE Balancing equations battleships
  • Jefferson Lab Balancing Act!
  • Science Geek Balancing Chemical Equations
  • CSUDH Balancing Chemical Reactions