Balancing Chemical Equations - Questions

The Balancing Chemical Equations Concept Builder is comprised of 36 questions. The questions are divided into 18 different Question Groups and spread across three difficulty levels. Questions in the same group are rather similar to one another. The Concept Builder is coded to select at random a question from each group until a student is successful with that group of questions.

There are three difficulty levels that can be engaged in through the Concept Builder. Those three levels are differentiated as follows:
 

• Apprentice Difficulty Level: Question Groups 1-6 ... Students are presented with a skeleton equation. They must enter coefficients in order to balance the equation. Each time a coefficient is changed, an Atom Count panel is updated. The panel shows the number of atoms of each element on reactant and product side of the equation. 
• Master Difficulty Level: Question Groups 7-12 ... Students are presented with a skeleton equation. They must enter coefficients in order to balance the equation. Students must also complete an Atom Count panel. The panel shows the number of atoms of each element on reactant and product side of the equation. The chemical equations are slightly more complicated than the ones in the Apprentice Difficulty Level.
• Wizard Difficulty Level: Question Groups 13-18 ... Students are presented with a skeleton equation. They must enter coefficients in order to balance the equation. An Atom Count panel is displayed and it is recommended (but not required) that students use. The panel shows the number of atoms of each element on reactant and product side of the equation. The chemical equations are slightly more complicated than the ones in the Apprentice and the Master Difficulty Level.

The questions from each group are shown below. Teachers are encouraged to view the questions in order to judge which difficulty levels are most appropriate for their classes. 

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Balancing Chemical Equations

 
Activity 1
Question Group 1
Question 1
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Al     +     Br₂     →      AlBr₃

 
 
Question 2
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Re     +     Br₂     →      ReBr₃

 
 
 
Question Group 2
Question 3
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Al   +    N₂  →     AlN

 
 
Question 4
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Fe   +    N₂   →     FeN

 
 
 

 
Question Group 3
Question 5
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Na      +       O₂    →    Na₂O

 
 
Question 6
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Li      +       O₂    →    Li₂O

 
 
 
Question Group 4
Question 7
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Na    +    Cl₂    →    NaCl

 
 
Question 8
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

Na    +    Br₂    →    NaBr

 
 
 

 
Question Group 5
Question 9
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

MnI₃      →       Mn     +      I₂

 
 
Question 10
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

PaI₅      →       Pa     +      I₂

 
 
 
Question Group 6
Question 11
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

C₃H₈    +   O₂    →    CO₂   +    H₂O

 
 
Question 12
Identify the lowest possible whole number coefficients that balance the chemical equation.
 

CH₄   +    O₂   →    CO₂   +    H₂O

 
 
 

 
Activity 2
Question Group 7
Question 13
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

N₂    +   H₂    →    NH₃

 
 
Question 14
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Ti       +          N₂    →    Ti₃N₄

 
 
 
Question Group 8
Question 15
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Mg    +   O₂    →    MgO

 
 
Question 16
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Ca    +   O₂    →    CaO

 
 
 

 
Question Group 9
Question 17
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Zn(OH)₂   +    H₃PO4   →     Zn₃(PO₄)₂   +    H₂O

 
 
Question 18
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Cu(OH)₂   +    H₃PO₄   →     Cu₃(PO₄)₂   +    H₂O

 
 
 
Question Group 10
Question 19
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

P     +      H₂O     →        PH₃     +     H₃PO₃

 
 
Question 20
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Sb     +      H₂O     →        Sb₂O₃     +     H₂

 
 
 

 
Question Group 11
Question 21
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

C₂H₆    +   O₂    →    CO₂   +    H₂O

 
 
Question 22
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

C₄H₁₀    +   O₂    →    CO₂   +    H₂O

 
 
 
Question Group 12
Question 23
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Al    +   AuCl    →    AlCl₃    +   Au

 
 
Question 24
Identify the lowest possible whole number coefficients that balance the chemical equation.  Then conduct an atom count for each element.
 

Al    +   AgCl    →    AlCl₃    +   Ag

 
 
 

 
Activity 3
Question Group 13
Question 25
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Al    +   ZnSO₄   →   Al₂(SO₄)₃    +    Zn

 
 
Question 26
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Al    +    CuSO₄     →     Al₂(SO₄)₃   +    Cu

 
 
 
Question Group 14
Question 27
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

H₂    +    Fe₂O₃    →     Fe  +    H₂O

 
 
Question 28
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Al    +   CuCl₂    →    AlCl₃    +   Cu

 
 

 
Question Group 15
Question 29
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

CH₃OH   +    O₂    →    CO₂   +    H₂O

 
 
Question 30
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

C₂H₅OH    +   O₂    →    CO₂   +    H₂O

 
 
 
Question Group 16
Question 31
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Al(OH)₃   →    Al₂O₃     +       H₂O

 
 
Question 32
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

P₂O₅    +   H₂O    →    H₃PO₄

 
 
 

 
Question Group 17
Question 33
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Fe₂O₃       +          CO    →    Fe      +         CO₂

 
 
Question 34
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

SiO₂   +    C    →   SiC    +    CO

 
 
 
Question Group 18
Question 35
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Ba(OH)₂        +       CO₂    →    BaCO₃       +          H₂O

 
 
Question 36
Identify the lowest possible whole number coefficients that balance the chemical equation.  
 

Ca(OH)₂        +       CO₂    →    CaCO₃       +          H₂O