Name: ______

Date: ______

SNC2P – Balancing Chemical Equations Using Marshmallow Models

Do NOT eat the marshmallows! They have been sprayed with chemicals.

The law of conservation of mass: During a chemical reaction, the total mass and number of atoms of the reactants ______the total mass and number of atoms of the products.

Balanced chemical equation: Is a chemical equation using ______that show how much of the reactants are used and how much of the products are made during a chemical reaction. (Coefficients are the numbers in front of the reactants and products)

MATERIALS:

-  20 toothpicks

-  15 pink marshmallows (Oxygen atoms)

-  10 orange marshmallows (Chlorine atoms)

-  10 yellow marshmallows (Carbon or Nitrogen atoms)

-  20 green marshmallows (Hydrogen atoms)

-  6 plates

EQUATIONS TO BALANCE:

1.  Mg + HCl → MgCl2 + H2

2.  H2 + Cl2 → HCl

3.  N2 + H2 → NH3

4.  H2 + O2 → H2O

5.  CO + O2 → CO2

6.  CH4 + O2 → CO2 + H2O

EQUATION #1 (Mg + HCl → MgCl2 + H2)

a)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

b)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
Mg
H
Cl

c)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

d)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.

EQUATION #2 (N2 + H2 → NH3)

a)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

b)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
N
H

c)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

d)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.

EQUATION #3 (H2 + Cl2 → HCl)

e)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

f)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
H
Cl

g)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

h)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.

EQUATION #4 (H2 + O2 → H2O)

a)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

b)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
H
O

c)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

d)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.

EQUATION #5 (CO + O2 → CO2)

a)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

b)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
C
O

c)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

d)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.

EQUATION #6 (CH4 + O2 → CO2 + H2O)

a)  Build both the reactants and products using the marshmallows and toothpicks. Make sure you use the correct marshmallows!

b)  Complete the following chart by counting the number of atoms:

Atoms / Reactants / Products
C
H
O

c)  When the number of each type of atom on the reactant side is equal to the number of each type of atom on the product side, complete the observation table on the last page.

d)  Call the teacher over to check your marshmallow model and balanced chemical reaction. You CANNOT go on to the next reaction until I have initialled this section of your assignment.

Teacher Initials: ______
After I have initialled this section, take your model apart and go on to the next equation.


OBSERVATION TABLE:

Instruction: Write out the balanced chemical equation and draw a diagram of your marshmallow models. For your diagram, it would be a good idea to use different colours to show the different types of atoms.

Equation / Balanced Chemical Equation and Diagram of Models
1 / Balanced Chemical Equation:
→
Diagram of Models:
→
2 / Chemical Equation:
→
Diagram of Models:
→
3 / Chemical Equation:
→
Diagram of Models:
→
4 / Balanced Chemical Equation:
→
Diagram of Models:
→
5 / Chemical Equation:
→
Diagram of Models:
→
6 / Chemical Equation:
→
Diagram of Models:
→