Stoichiometry Fireworks Lab Quiz
Given the amount of one reactant, students must use stoichiometry to find the ideal amount of the second reagent to use to create purple fireworks. The teacher ignites each groups' fireworks. Ideal mixture create little or no ash. Student assignment sheet with directions (and different initial amounts) plus teacher information and sample answers are included. This is an exciting and engaging activity that can be used as a stoichiometry quiz.
These worksheets are part of a entire unit on teaching stoichiometry. You can access the complete lesson plans with information on their use, and links to other worksheets, labs, and activities at https://www.chemedx.org/article/stoichiometry-easy.
Materials
Student materials:
- 1 - 100 mL beaker
- 1 - 250 mL beaker
- Vial of potassium chlorate (KClO3)
- Vial of sugar (C12H22O11)
- Stirring rod
- Wax pencil
- Centigram balance (ideally one for each lab table).
- goggles
Teacher Materials:
- Fireproof board
- Bunsen burner (with long hose)
Background
This experiment is best done in groups of two. Students should have learned how to do stoichiometry problems, be experienced in using a balance, and be able to follow basic directions.
For this lab quiz students are given a specified amount of one reactant (the limiting reactant), and must complete the correct stoichiometry calculation to determine the ideal amount of the other reactant. They are instructed to show all their work.
In a fume hood, the teacher ignites each groups' mixture. Ideally, there are purple flames and sparks and very little white "ash." An excess of sugar results in production of carbon "worms." And excess of potassium chlorate does not burn well and is difficult to ignite.
Procedure
See the student lab sheet.
Questions
See the student lab sheet.
Concepts
Stoichiometry, limiting reactant, laboratory measures
Time Required
With one balance per table (two groups), the calculations should take about 10 minutes, the measures another 10 minutes. Ideally, students should be prepared to deliver their mixture to the teacher within 20 minutes. In practice, many students will take longer, particularly if the formula for potassium chlorate is not given and students are not familiar enough with ionic nomenclature.
The teacher will need about one minute per group to announce the group's mixture, ignite it, and wait for student responses. So if there are 15 groups, the teacher should allow about 15 minutes to ignite all the mixtures.
Preparation
Each table (two groups) needs one balance and one vial of each reagent plus a 100 mL and a 250 mL beaker for each group (two of each beaker). It is convenient to have all the student materials placed in a tub or basket. Each table also should have a centigram balance, if possible. If more than two groups must share a balance, the lab quiz may take more time than is available.
Attribution
David P. Licata, Pacifica High School, Garden Grove, CA (retired)
Credits
Mr. Courtney Lantz, Pacifica High School, Garden Grove, CA (retired) contributed to the development of this lab experiment.
Supporting Information
General Safety
For Laboratory Work: Please refer to the ACS Guidelines for Chemical Laboratory Safety in Secondary Schools (2016).
For Demonstrations: Please refer to the ACS Division of Chemical Education Safety Guidelines for Chemical Demonstrations.
Other Safety resources
RAMP: Recognize hazards; Assess the risks of hazards; Minimize the risks of hazards; Prepare for emergencies
DAVID LICATA
I taught chemistry at all levels from grade three through community college. Thirty-three years were spent teaching four levels of high school chemistry (non-math descriptive chemistry through Advanced Placement).
Comments
12Exciting
I was immediately thrilled about this Lab Quiz!
I am going to do the quiz the last lesson before the Christmas Holidays.
Thank you for sharing this!
Maria Kraakman
Chemistry teacher
Cartesius Lyceum
Amsterdam, The Netherlands
In reply to Exciting by Maria Kraakman…
More Stoichiometry items coming
Thanks for the kind comment.
Look for more items, including a specifically Christmas-themed (though algorithmic) aid to learning how to do stoichiometry. Not sure how it will translate into Norwegian, but perhaps your own creativity will find a way to make it work. I am slowly getting my entire stoichiometry unit of worksheets, labs (which are done), collaborative activities, and the Christmas-themed aid uploaded. I am working with the ChemEdX staff to get through some issues with uploading, formatting, and so on, so the work is going slowly. Eventually everything will be linked to a single article that describes the lesson plans I used for nearly 30 years. I hope you will enjoy them.
I hope that you and your students will have fun with this activity. I always promote it several days in advance by telling students that those who do the best will end up with only a small amount of salt, but those who do poorly will be obvious due to the "big ash-sh-sh-sh-sh-huh" that they have -- this takes advantage of the close correspondence in sound between the English word "ash" and the English word for a person's back side. Of course it generates smiles and a few snickers -- and a few more when students see a group that does leave a lot of burnt sugar ash. Again, not sure how that will translate, but we have fun with it.
Oxidation numbers
This excercise would also be good practice for students to balance redox reactions based on the change in oxidation numbers of C and Cl. On another note, this mixture can also be self-ignited with a small amount of concentrated sulfuric acid but that would undoubtedly also produce some carbonaceous by-product due to the exothermic decomposition of some of the sugar (like in the carbon sausage demo). I wonder if that variation would give similar results (i.e. very little ash except for a tiny bit of carbonaceous by-product produced).
Stoichiometry quiz
Thank you so much. A good idea which looks like fun and I look forward to using it soon!
Caroline Lehman
Stoichiometry unit
Thank you so much for your great ideas. I have been teaching for a long while, but am always looking for ideas and ways to improve. As soon as I get a free minute (Christmas break?), I am going to take a closer look at this.
Take a look over Thanksgiving break
Thanks for the comment. I am sure your students will find the lab fun, and the "competition" exciting. Let me suggest that you take a look at the lab, and my article on how I taught stoichiometry during your Thanksgiving break (well, if you are in the US -- other than turkey and football, you won't have anything else to do, will you??).
The entire article and links to all the other materials I used is at:
http://www.jce.divched.org/article/stoichiometry-easy
You will find more items there, some that you might want to start using before Christmas.
D.
Finally used this with my students today!
I finally did this "fireworks lab quiz" with my students today! It was a great formative and summative assessment. Students wanted their firework to work, so they kept persevering through the stoichiometry, and in the end, I only had a few groups throughout the whole day who were unsuccessful (and that was because they gave up, not because they made a mistake). Thank you so much for posting this!
Glad your students enjoyed it. I have used it when I subbed at several schools since retiring, and it is always a hit.
Great Stoichiometry Lab
I have used this as a lab for stoichiometry with my honors chemistry students the last 2 years. The calculations (including balancing the equation) are challenging, and the students did a great job! Igniting the fireworks is awesome!
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