Lesson 7: Introduction to Balancing Chemical Equations

Balancing Chemical Equations
Objectives:  Students will...
explain what chemists mean when they say an equation is balanced.
balance chemical equations.

Part 1: PhET Simulation
To start investigating how to balance chemical equations, spend a few minutes playing with the 'Introduction' screen in the simulation below.  Make sure to check out the tools and figure out what they do. 

DIRECTIONS: Once you're done exploring the 'Introduction' screen, use the simulation to answer questions 1-5 . 

1

Balance the 'Make Ammonia' reaction. How many total molecules are on the reactants and products side?

1

Balance the 'Make Ammonia' reaction. How many total atoms are on the reactants and products side?

1

Balance the 'Separate Water' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

2 molecule
3 molecules
6 molecules
1 atom
2 atoms
3 atoms
6 atoms
9 atoms

Reactant side
Product side

1

Balance the 'Combustion of Methane' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

1 molecule
2 molecules
3 molecules
1 atom
2 atoms
4 atoms
6 atoms
9 atoms

Reactant side
Product side

1

Which of the following statements about balanced chemical equations is correct?

1

Consider the equation from the 'Making Ammonia' example:

What are the numbers in green and blue called, and what do they represent?

Coefficients
Subscripts
The number of molecules involved in the reaction
The number of a specific type of atom.

Green Numbers
Blue Numbers

1

Which of the following coefficients could you use in a balanced chemical equation?

1

If you were balancing an equation containing an O2 molecule, which of the following would be correct representations of O2 and its coefficient?

1

Examine equation a and equation b below. Both are balanced, but equation b is the correct way to write a balanced equation:

Answer the following questions:
What is the relationship between the coefficients in equations a and b?
Why is equation b considered the correct way to write the balanced chemical equation?

1

Play Level 1 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Write down two strategies that you used to balance chemical equations.

1

Play Level 2 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
What do you find most difficult about balancing chemical equations so far?

1

Play Level 3 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Are there any other strategies you found for balancing?

Lesson 7: Introduction to Balancing Chemical Equations

Balancing Chemical Equations

Part 1: PhET Simulation

Balance the 'Make Ammonia' reaction. How many total molecules are on the reactants and products side?

Balance the 'Make Ammonia' reaction. How many total atoms are on the reactants and products side?

Balance the 'Separate Water' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

Balance the 'Combustion of Methane' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

Which of the following statements about balanced chemical equations is correct?

Consider the equation from the 'Making Ammonia' example:What are the numbers in green and blue called, and what do they represent?

Which of the following coefficients could you use in a balanced chemical equation?

If you were balancing an equation containing an O2 molecule, which of the following would be correct representations of O2 and its coefficient?

Play Level 1 of the Balancing Equation game. Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)Write down two strategies that you used to balance chemical equations.

Play Level 2 of the Balancing Equation game. Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)What do you find most difficult about balancing chemical equations so far?

Play Level 3 of the Balancing Equation game.Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)Are there any other strategies you found for balancing?

Balancing Chemical Equations

Part 1: PhET Simulation

Balance the 'Make Ammonia' reaction. How many total molecules are on the reactants and products side?

Balance the 'Make Ammonia' reaction. How many total atoms are on the reactants and products side?

Balance the 'Separate Water' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

Balance the 'Combustion of Methane' reaction. How many total molecules and how many total atoms are on each side of the balanced equation?

Which of the following statements about balanced chemical equations is correct?

Consider the equation from the 'Making Ammonia' example:What are the numbers in green and blue called, and what do they represent?

Which of the following coefficients could you use in a balanced chemical equation?

If you were balancing an equation containing an O2 molecule, which of the following would be correct representations of O2 and its coefficient?

Play Level 1 of the Balancing Equation game. Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)Write down two strategies that you used to balance chemical equations.

Play Level 2 of the Balancing Equation game. Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)What do you find most difficult about balancing chemical equations so far?

Play Level 3 of the Balancing Equation game.Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)Are there any other strategies you found for balancing?

Consider the equation from the 'Making Ammonia' example:

What are the numbers in green and blue called, and what do they represent?

Play Level 1 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Write down two strategies that you used to balance chemical equations.

Play Level 2 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
What do you find most difficult about balancing chemical equations so far?

Play Level 3 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Are there any other strategies you found for balancing?

Consider the equation from the 'Making Ammonia' example:

What are the numbers in green and blue called, and what do they represent?

Play Level 1 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Write down two strategies that you used to balance chemical equations.

Play Level 2 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
What do you find most difficult about balancing chemical equations so far?

Play Level 3 of the Balancing Equation game.
Take a screenshot of your score and put it in the 'Show Your Work' box below. (Don't know how to take a screenshot? Click here to find out how!)
Are there any other strategies you found for balancing?