TEKS 8.5D recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in
chemical formulas containing subscripts
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
Beady Balance
Materials:
 bingo chips
Objectives:
 Determine the number of atoms of each element in a chemical formula
containing subscripts.
 Recognize whether a chemical equation containing coefficients is balanced.
 Relate a balanced equation to the law of conservation of mass.
Element
H
Cl
O
N
C
Na
Fe
Teacher Directions:
 Distribute bingo chips to each student group
according to the chart.
 Using the bingo chips, model the equation
Na + Cl2
 Since this equation is not balanced, instruct
students to place an “X” in the box next to
the equation.
Questions:
1. X
Na
+
2. 
2Na
+
2H20 => 2NaOH
3. 
2CO
+
2NO =>
4. X
Fe2O3 +
5. X
C
+
Cl2 =>
CO
=>
Fe2O3
=>
Color
Blue
Red
Yellow
Green
Orange
Pink
Purple
Quantity
8
3
8
4
4
4
3
NaCl
2CO2
Fe
CO
+
+
+
+
H2
N2
CO2
Fe
6. In order to balance an equation, here are the steps that must be taken:
Count the number of atoms on each side of the equation. Add
coefficients to balance the number of atoms on each side of the yield
sign. Check to be sure the number of atoms for each element is equal.
7. If an equation is balanced, then the number of atoms in the reactants and the
number of atoms in the products are equal.
8. The law of conservation of mass tells us that atoms and mass cannot be
created or destroyed. Therefore, the mass of the reactants and products will
also be equal.
10.
11.
12.
13.
14.
15.
modeled for students
4 Al + 3O2  2Al2O3
4Cu + O2  2Cu2O
2H2 + O2  1H2O
2Fe + 3Cl2  2FeCl3
2Al + 3S  Al2S3
9.
coefficient
Fe + 2 HCl
chemical symbol
subscript
FeCl2 + H 2
yield sign
chemical formula
TEKS 8.5D recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas
containing subscripts
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
Beady Balance
Objectives:
 Determine the number of atoms of each element in a chemical formula
containing subscripts.
 Recognize whether a chemical equation containing coefficients is balanced.
 Relate a balanced equation to the law of conservation of mass.
Directions:
1. The table shows the color of bingo chip used to represent each element.
You will need the number of chips shown for each color.
Element
H
Cl
O
N
C
Na
Fe
Color
Blue
Red
Yellow
Green
Orange
Pink
Purple
Quantity
8
3
8
4
4
4
3
2. Watch and follow along as your teacher models the first equation,
Na + Cl2

NaCl.
3. Answer the questions that follow. You may use the bingo chips to help
you with your answers.
Questions:
Place a check mark if the equation is balanced. Mark an X if the equation is not balanced.
1.__
2. __
3.__
_
Na
+
Cl2 =>
2Na
+
2H20 => 2NaOH
2CO
+
2NO =>
Fe2O3 +
4. __
C
5. __
+
CO
Fe2O3
=>
=>
NaCl
2CO2
Fe
CO
+
+
+
+
H2
N2
CO2
Fe
6. In order to balance an equation, here are the steps that must be taken:
_____________________________________________________________
_____________________________________________________________
_____________________________________________________________
7. If an equation is balanced, then the number of _______________ in the
reactants and the number of atoms in the _________________ are equal.
8. The law of ____________________ of mass tells us that atoms and
mass cannot be _______________ or destroyed. Therefore, the
____________ of the _________________ and products will also be equal.
9. Label the parts of the chemical equation.
_______________
chemical equation
Fe + 2 HCl
________ __________
____________
____________
FeCl2 + H2
____________ _________
Al
10. – 15. Use the key at the right to write a chemical equation
using the correct chemical symbols, subscripts and
coefficients. The first one is completed for you.
(Hint: if the symbols are touching, the atoms are chemically bonded.
If the symbols are not touching, individual molecules are
represented.)
O
Cu
H
Fe
Cl
S
+
=>
+
2 Cu + 2 HCl
10
.
+
=>
11
.
+
=>
+
=>
12
.
13
.
+
=>
14
.
+
15
.
=>
=> 2 CuCl + H2