1. Balancing Chemical Equations
Created by Kesler Science – More 5E lessons at KeslerScience.com
Presented by Kesler Science

2. Essential Questions:
What are the different parts of the chemical equation?
How can we tell if a chemical equation is balanced or not?
How does balancing equation relate to the law of conservation of mass?

3. Quick Action – INB Template
Directions for INB Template
Fold the paper along the dotted line.
Cut on the lines between each word up to the dotted line.
Paste the blank half of the page into your INB so that the flaps open up.
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4. 2 H2O Review Balancing Chemical Equations
Subscripts describe the # of atoms in a molecule
H2O Model
The Coefficient represents the number of molecules
2 Molecules of H2O 2
H2O H O H O
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5. 2H2 + O2  2 H2O Chemical Equation Balancing Chemical Equations
Broken into 3 main parts
Reactants
Arrow = Chemical Reaction
Products
RAP is an easy way to remember.
2H2 + O2  2 H2O
Reactants
Product
Arrow
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6. 2H2 + O2  2 H2O Reactants Balancing Chemical Equations
Elements or compounds which exist PRIOR to a chemical reaction
4 atoms of Hydrogen
2 atoms of Oxygen
2H2 + O2  2 H2O
Reactants
Students should take these notes on the INB template.
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7. 2H2 + O2  2 H2O Products Balancing Chemical Equations
New substances that are created by the rearranging of atoms after a chemical reaction
2 molecules of water
4 hydrogen atoms
2 oxygen atoms
2H2 + O2  2 H2O
Product
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8. 2H2 + O2  2 H2O Arrow/Chemical Reaction Balancing Chemical Equations
The arrow represents a chemical reaction.
Atoms are rearranged to form new substances
Atoms are not lost or gained; they must be equal on both sides
2H2 + O2  2 H2O
Arrow
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9. 6CO2 + 6H2O  C6H12O6 + 6O2 Quick Action
Work with a partner to find the following items:
List the Products
List the Reactants
What does the arrow Represent?
How many atoms of oxygen are on the product side?
How many atoms of hydrogen are on the reactant side?
BONUS: What process does this chemical reaction represent?
Answers:
C6H12O6 and O2
CO2 and H2O
Chemical reaction or chemical change 18 12
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10. Law of Conservation of Mass
Balancing Chemical Equations
Law of Conservation of Mass
Matter (atoms) can neither be created  nor destroyed.
Atoms can only be rearranged.
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11. Balancing Chemical Equations
Equal number of the same type of atom on each side.
If unbalanced, you can only change the coefficient to make it balanced.
You CANNOT change subscripts.
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12. 2 Ag2O g Ag + O2 4 2 Balanced! Balancing Chemical Equations Practice
Step 1 – Take Inventory of the elements and atoms on the product and reactant side. Step 2 – Is it balanced? Step 3 – If unbalanced, change coefficients until it’s balanced. 2
Ag2O g Ag O2 4 2
Ag – 2 O – 1 4 =
Ag – 1 O – 2 4 2 2
As of 2016 the Texas standards says student are to “recognize if a chemical equation is balanced using coefficients”.
For your on-level classes you could stop here. It’s either balanced or it isn’t.
For your advanced classes you could actually teach them how to balance the equation.
Balanced!
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13. CH4 + Cl2  CCl4 + HCl 4 4 Balanced!
Balancing Chemical Equations Practice
Step 1 – Take Inventory of the elements and atoms on the product and reactant side. Step 2 – Is it balanced? Step 3 – If unbalanced, change coefficients until it’s balanced.
CH4 + Cl2  CCl4 + HCl 4 4
C – 1 H – 4 Cl – 2 =
C – 1 H – 1 Cl – 5 4 8 8
As of 2016 the Texas standards says student are to “recognize if a chemical equation is balanced using coefficients”.
For your on-level classes you could stop here. It’s either balanced or it isn’t.
For your advanced classes you could actually teach them how to balance the equation.
Balanced!
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14. Quick Action – INB Template
Directions for INB Template
Cut the paper out along the solid line.
Determine if the formulas are balanced or unbalanced.
Paste the template into your INB.
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15. Quick Action – Balance the Equation
Step 1 – Take Inventory of the elements and atoms on the product and reactant side.
Step 2 – Is it balanced?
Step 3 – If unbalanced, change coefficients until it’s balanced.
NaBr + CaF2  NaF + CaBr2
Allow students to work with a partner
Answer: 2NaBr +CaF2  2NaF + CaBr2
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16. Quick Action – INB Template
Directions for INB Template
Cut out the INB template.
Do not cut the dashed lines
Paste them into your INB along the skinny tab so that the template folds up like an accordian.
I would only do this sheet in your advanced class unless you have to teach HOW to balance equations rather than determining if it is balanced or not.

17. Check for Understanding
Can you…
Recognize whether a chemical equation balanced or not?
Relate balanced equations to the law of conservation of mass.
Clear up any confusion and answer questions.
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