ALEX Lesson Plan


Balancing Chemical Reactions

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  This lesson provided by:  
Author:Brenda Rinehart
System: Shelby County
School: Shelby County Board Of Education
  General Lesson Information  
Lesson Plan ID: 26242


Balancing Chemical Reactions


Students will participate in a guided inquiry activity using manipulatives to learn how to balance chemical reactions.

This activity was developed in cooperation with Michelle Holdbrooks at Thompson High School (

 Associated Standards and Objectives 
Content Standard(s):
SC (9-12) Physical Science
4. Use nomenclature and chemical formulas to write balanced chemical equations.
  • Explaining the law of conservation of matter
  • Identifying chemical reactions as composition, decomposition, single replacement, or double replacement
  • Defining the role of electrons in chemical reactions
  • SC (9-12) Chemistry
    6. Solve stoichiometric problems involving relationships among the number of particles, moles, and masses of reactants and products in a chemical reaction.
  • Predicting ionic and covalent bond types and products given known reactants
  • Assigning oxidation numbers for individual atoms of monatomic and polyatomic ions
  • Identifying the nomenclature of ionic compounds, binary compounds, and acids
  • Classifying chemical reactions as composition, decomposition, single replacement, or double replacement
  • Determining the empirical or molecular formula for a compound using percent composition data
  • SC2015 (9-12) Physical Science
    5. Use mathematical representations to support and verify the claim that atoms, and therefore mass, are conserved during a simple chemical reaction.
    SC2015 (9-12) Chemistry
    5. Plan and conduct investigations to demonstrate different types of simple chemical reactions based on valence electron arrangements of the reactants and determine the quantity of products and reactants.
    a. Use mathematics and computational thinking to represent the ratio of reactants and products in terms of masses, molecules, and moles.
    b. Use mathematics and computational thinking to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.

    Local/National Standards:

    National Science Education Standards (NSES) as correlated by the National Research Council (NRC).

    NSES Content Standard B
    Physical Science: Chemical reactions
    Grades 9-12

    Chemical reactions occur all around us, for example in health care, cooking, cosmetics, and automobiles. Complex chemical reactions involving carbon-based molecules take place constantly in every cell in our bodies.

    NSES Content Standard B
    Physical Science: Chemical reactions
    Grades 9-12

    Chemical reactions may release or consume energy. Some reactions such as the burning of fossil fuels release large amounts of energy by losing heat and by emitting light. Light can initiate many chemical reactions such as photosynthesis and the evolution of urban smog.

    NSES Content Standard B
    Physical Science: Chemical reactions
    Grades 9-12

    A large number of important reactions involve the transfer of either electrons (oxidation/reduction reactions) or hydrogen ions (acid/base reactions) between reacting ions, molecules, or atoms. In other reactions, chemical bonds are broken by heat or light to form very reactive radicals with electrons ready to form new bonds. Radical reactions control many processes such as the presence of ozone and green-house gases in the atmosphere, burning and processing of fossil fuels, the formation of polymers, and explosions.

    Primary Learning Objective(s):


    Additional Learning Objective(s):

     Preparation Information 

    Total Duration:

    Time Not Specified

    Materials and Resources:

    card stock, plastic baggies, 3.5" x 5" labels, variety of colors of interlocking blocks (colored paper clips, colored paper, magnetic discs, etc. can be used in place of the interlocking blocks)

    1. The teacher will need to print in color the reaction cards on white card stock.
    2. The teacher will need to prepare the baggies with the interlocking blocks or substitutes for the blocks according to the baggie labels.
    3. It is best if the teacher makes an extra set of one reaction to demonstrate how to use the manipulatives to learn balancing equations. This can either be with an interactive board, magnetic colored blocks on a dry erase board, or interlocking blocks using an ELMO.

    The preparation time for this activity is about 10 hours. Student and parent workers can easily prepare this activity.

    Technology Resources Needed:

    color printer

    Optional: computer, LCD projector, interactive whiteboard, ELMO


    The teacher should be familiar with the concepts of chemical nomenclature, diatomic molecules (H2, O2, N2, F2, Cl2, Br2, I2), reaction symbols, reaction types, and balancing equations.

    1. Divide students into diverse ability groups of three to four students.  It is best if the students have tables or flat desks for this activity.
    2. Give each group the twelve different reaction baggies and the baggie with the reaction picture cards.
    3. Each student should select three or four reactions.
    4. Select one reaction (the one you have prepared as the teacher demonstration) and direct the student to build one example of each reactant and each product.
    5. The students will notice the bag contains \"extra\" blocks. These blocks are the ones needed to balance the equation.
    6. Guide the students in building additional molecules until all the blocks are used and each side of the reaction has the same number and color of blocks.  This will show the students the number of reactant molecules or moles needed to produce the correct number of product molecules or moles.
    7. The students are to write the number of molecules or moles of each reactant and product in the blanks to the left of the reactant or product on the activity sheet.
    8. Students will then proceed to balance the remaining equations by building the reactants and products and using all the blocks to determine how many molecules or moles of each reactant and product will balance the equation. 
    9. A PowerPoint is attached to use as a summary review of balancing equations and provide more practice for the students.

    **Some files will display in a new window. Others will prompt you to download.

    Assessment Strategies

    • Activity worksheet - group or individual


    1. ChemBalance
    2. Creative Balancing
    3. Even more practice

    Students can practice online balancing equations either individually or as a group.


    Students who are having trouble balancing equations can use the following websites to check extra practice problems and to learn another approach to balancing equations:

    1. Equation Checker
    2. Equation Tutorial

    Each area below is a direct link to general teaching strategies/classroom accommodations for students with identified learning and/or behavior problems such as: reading or math performance below grade level; test or classroom assignments/quizzes at a failing level; failure to complete assignments independently; difficulty with short-term memory, abstract concepts, staying on task, or following directions; poor peer interaction or temper tantrums, and other learning or behavior problems.

    Presentation of Material Environment
    Time Demands Materials
    Attention Using Groups and Peers
    Assisting the Reluctant Starter Dealing with Inappropriate Behavior
    Be sure to check the student's IEP for specific accommodations.