Balancing Chemical
Equations
1) TEKS: 8.5F recognize whether a chemical equation containing coefficients
is balanced or not and how that relates to the law of conservation of mass.
Prior Knowledge:
Students should be able to define atoms, elements, molecules, and compounds before beginning this
assignment. They should also have a general understanding of the periodic table of elements.
Lesson objectives
Teachers' notes
Teacher's notes con't
Subject: Chemistry
Grade(s):
Topic: Chemical Equations
Cross-Curricular Links:
8
.
Lesson notes:
Intended Learning Outcome:
This lesson is an introduction to balancing chemical equations. This assignment helps show how compounds are
a unit and can be added only as groups.
Instructions:
Each slide contains a chemical equation. Students are to balance the equation by cloning the graphic element boxes
so that there are equal amounts of all atoms on both sides. When this is accomplished, the coefficients should be
written in the equation.
Slide 5 contains a video tutorial on balancing equations. The video solves the same chemical equation shown on
that slide.
Lesson Objectives
Teacher's notes
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Lesson notes continued:
__H
The compounds/molecules are already created on each slide; however, the teacher could choose to build them
with his or her students to represent how the atoms are grouped.
Edited by: Lisa Jackson, ITS, NEISD
Authored by: Bret Gensburg, University of Akron
Lesson Objectives
Teacher's notes
Teacher's notes con't
Pull here for molecule and equation samples
Optional Enhancement:
EXAMPLE: Balance the following equation. A balanced equation has the same number of atoms of
each element on both sides of the equation. Clone the molecules which contain atoms of which
you do not have enough. Then count the molecules and write the coefficient in the chemical
equation.
__H2 +__O2
__H2O
Video Tutorial
Work through this sample together, or click on
the video file below to watch, listen, and learn
how to balance a chemical equation.
balancing chemical equations.avi
Answer
2H2 + O2
2H2O
Balance the following equation so that there are the same number of atoms on each side of the yield
sign. (Clone the molecules as needed.) Click on the answer box to reveal the answer. What numbers
should be added to the equation, if any? Write them in the spaces below.
__CaCO3
__CaO + __CO2
Answer
CaCO3 CaO + CO2
Balance the following equation.
__C + __Cl2
__CCl4
Answer
C + 2Cl2
CCl4
Balance the following equation.
__H2 + __Cl2
__HCl
Answer
H2 + Cl2 2HCl
Balance the following equation.
__Na + __F2
__NaF
Answer
2Na + F2
2NaF
Balance the following equation.
__H2O2
__H2O + __O2
Answer
2H2O2 2H2O + O2
Balance the following equation.
__KClO3
__KCl + __O2
Answer
2KClO3
2KCl + 3O2
Balance the following equation.
__P + __O2
__P4O10
Answer
4P + 5O2
P4O10
Balance the following equation.
__BaCl2 + __H2SO4
__BaSO4 + __HCl
Answer
BaCl2 + H2SO4
BaSO4 + 2HCl
Balance the following equation.
__N2 + __H2
__NH3
Answer
N2 + 3H2
2NH3
Balance the following equation.
__Na + __Cl2
__NaCl
Answer
2Na + Cl2
2NaCl
Balance the following equation.
__Fe + __O2
__Fe2O3
Answer
3Fe + O2
Fe2O3