Balancing Chemical Equations
Load the simulation Balancing Chemical Equations http://phet.colorado.edu/en/simulation/balancing-chemical-equations
Critical Thinking Questions
Explore the Balancing Chemical Equations simulation.
- What are the different ways that the simulation indicates when an equation is balanced?
For each balanced reaction, indicate the total number of molecules in the table below.
| Reaction | Total Number of Molecules | |
| Reactant Side (Left) | Product Side (Right) | |
| Make Ammonia | ||
| Separate Water | ||
| Combust Methane | ||
Is the number of total molecules on the left side of a balanced equation always equal to the number of total molecules on the right side of the equation? Explain your answer.
For each balanced reaction, indicate the total number of atoms in the table below.
| Reaction | Total Number of Atoms | |
| Reactant Side (Left) | Product Side (Right) | |
| Make Ammonia | ||
| Separate Water | ||
| Combust Methane | ||
Is the number of total atoms on the left side of a balanced equation always equal to the number of total atoms on the right side of the equation?
What is the same on the left and right side of a balanced equation? Explain your answer.
Play level 1 of the balancing equation game. Write down the strategies you used to balance chemical equations.
Start level 2 of the balancing equation game using your strategies from Level 1, and adding new strategies as needed.
In the simulation, were you able to use noninteger numbers (like ½ or 0.43) for the coefficients in a balanced equation? Why do you think this is?
- Which of the following are coefficients you could use in a balanced equation?
☐ ½ ☐ ¾ ☐ 1 ☐ 2 ☐ 6 ☐ 9
- If you were balancing an equation containing the O2 molecule, which of the following would be correct representations of O2 and its coefficient?
☐ ½O2 ☐ O2 ☐ 3O2 ☐ 6O2 ☐ 3O ☐ 5O3
What do you have to do to the coefficients of equation I below to get to equation II?
- 2 SnO2 + 4 H2 🡪 2 Sn + 4 H2O
- SnO2 + 2 H2 🡪 Sn + 2 H2O
Both equation I and II are balanced, but is equation I the only correct way to write the balanced equation?
Can you divide equation II by another factor and still have it be correct? Why or why not?
In a complete sentence, write down a method you could use to determine if an equation is written in the correct way.
