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Hello All, I am currently teaching stoichiometry but am having a hard time motivating the students to learn the topic. Students do not want to learn the math portion of chemistry and this is making it very hard for the students to learn. I am trying to link stoichiometry to students experiences and interests but I am having a hard time. Could anyone help me with any resources that I could use for my students? Thank you in advance.

Sung Yi wrote, 'Students do not want to learn the math portion of chemistry and this is making it very hard for the students to learn. I am trying to link stoichiometry to students experiences and interests but I am having a hard time'

Hi Sung Yi,

In the past, I have had my students make cookies and we analyze the recipe. You provide them with a handout of the recipe with the amount of the ingredients in moles. Students have to convert to recipe's ingredient amounts to grams. They can then use a kitchen scale to measure the ingredients. You could also have them convert from moles to grams to cups, if you don't have a kitchen scale. It helps them relate stoichiometry to a real-world setting since most of your students should have some experience with cooking.
We do this activity in another room. One should be very careful about eating in the lab. I try to schedule a room switch with our FACS teacher so we have a kitchen to mix the dough and bake the cookies.

You can also use this activity to determine limiting reagents.

Another resource you might check out is the CHEM Matters magazine
which is published by the American Chemical Society.

I set it up as a forensic type problem or industry scenario. The students seem more interested in finding the answer to the problem if there's a realistic problem they're trying to solve. Even my kiddos who fight me on the math portion of chemistry seem to get interested in spite of themselves.

Meredith wrote, 'I set it up as a forensic type problem or industry scenario.'

Hi Meredith,

Could you give some more details about how you approach stoichiometry as a forensic or industrial scenario? Perhaps post the lab or activity you use?

Thanks, Ruth

Well, so far it's purely theoretical, all on paper. I hope to come up with a lab version of it some day. I basically disguise a regular stoics problem as a forensic situation or industrial scenario. For example, you are a quality control company attempting to determine effectiveness of a new technique to produce . . . Whatever, Titania was my most recent compound. The group you're observing used 570g titanium III acetate and 40L oxygen gas. If they produced 87g of product, how effective is their process? How much titanium III acetate must be used to react all of the oxygen gas? I have them discuss percent error and yield as well. Nothing fancy, just asking them to think about stoich in terms of industrial applications. I have an activity called "mole airlines" that covers empirical formulas from the perspective of a csi interpreting mass spec data. The kids get really into it if you make it a competition-winning a company contract or catching a killer, maybe throw in a prize for the winner or best presentation.

I try to use some real life examples that are similar to stoichiometry before I get into the actual chemistry problems. For example, I use different exchange rates for money as a method to solve a problem. If there are 12 pesos in a dollar and 70 yen in a dollar, then how many pesos are 100 yen? I show them how to set up the proporitions using money before I start molar mass/mole proportions. I also, do a simple mole ratio lab for them to see how a balanced chemical equation is used in stoichiometry. The mole ratio lab combines baking soda and hydrochloric acid to form salt, water, and carbon dioxide. I have the students evaporate the water and compare the mass of baking soda to the salt produced. R Kevin Tenison

I really like the money conversion analogy. I believe that most students would be able to relate that real-world example.

I had a request to attach the cookie lab I use. I did not write this lab myself and I cannot remember where I found it. I apologize to the author for not being able to give proper credit. I love this cookie lab because you could modify it for almost any recipe. You do not have to use chocolate chip cookies since the chemical formulas for other ingredients are given. The limiting reagent lab that is also attached is based on a lab from the 1999 edition of Holt's Modern Chemistry. The Learning Center also has another version of this lab that is made with sugar cookies. It can be found in the collection I attached.

Attachments

cookie_limiting_reagent_lab.rtf (0.02 Mb)

CookieChocolateChip.pdf (0.03 Mb)

Chemical Reactions Collection (6 items)

Podcast: Using Stories to Teach Chemistry: Chemical Reactions: Making and Breaking Bonds

- Podcast

Science Sampler: The Octet Rules-- A dating game for atoms

- Journal Article

Science Sampler: Chemistry in action—Triple delight

- Journal Article

View All 6 Items

I liked this piece from the Journal of Chemical Education. The activity introduces students to the concept of reduction- oxidation (redox) reactions. To help students obtain a thorough understanding of redox reactions, the concept is explored at three levels: macroscopic, submicroscopic, and symbolic. In this activity, students perform hands-on investigations of the three levels as they work at different stations that support examination and discovery of the general ideas in redox reactions, including oxidizing and reducing agents, and the stoichiometry of a reaction. It really helps to connect concepts.

Attachments

Redox_Reactions_in_Three_Representations.pdf (4.03 Mb)

Here is another activity that considers the stoichiometry of calcium supplements. I think this could be an effective way to connect stoichiometry to "real world" experience.

Attachments

Stoichiometry_of_Calcium_Medicines.pdf (0.12 Mb)

I see that the cooking idea has already been suggested but I will add another version of this Learning Stoichiometry with Hamburger Sandwiches.

Attachments

Learning_Stoichiometry_with_Hamburger_Sandwiches.pdf (0.06 Mb)

Here are three more activities that I think might engage your students. In "Lego Stoichiometry" Lego building blocks are used to explore the relationship between mass and number. Students discover and develop the concepts of limiting reagents and reactants in excess. Fizzy Drinks shows a very practical use of stoichiometry--that of making a carbonated drink similar to the popular Fizzies tablets that are added to water. How big is the ballon T focuses on a familiar reaction, that of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar). Students discover the concept of stoichiometry and limiting reactants in two ways: first by adding vinegar to a small quantity of baking soda until bubbles stop, and second by mixing a constant quantity of baking soda with increasing volumes of vinegar and collecting the carbon dioxide produced in balloons.

Attachments

Lego_Stoichiometry.pdf (0.11 Mb)

Sorry but I have no idea why I am having problems uploading files. Let me try again

Attachments

Fizzy_Drinks_Stoichiometry_You_Can_Taste.pdf (0.24 Mb)

It seems that I have to do this one at a time. Here is the last one

Attachments

How_big_is_the_balloon.pdf (0.20 Mb)

Thank you all for your help. I was thinking about tying in stoichiometry with students interests and experiences. I think I will try the baking cookies lab but maybe just use the scenario.

Meredith wrote, 'I have an activity called 'mole airlines' that covers empirical formulas from the perspective of a csi interpreting mass spec data.'

Hi Meredith,

I was rereading through the thread and saw your reference to the empirical formulas activity. I would be interested in seeing it if you would share. Could you upload a copy? Empirical formula is a concept with which many beginning chemists struggle and I am always looking for great activities that will help them.

Thanks!
Ruth

Stoichiometry is my favorite topic in chemistry! My students definitely may not agree, but I try to get them excited about it. I always relate stoichiometry to food; for example, making an ice cream sundae, a sandwich, or -- the kids' favorite -- s'mores! I introduce quantities first... "A class of small, ravenous children storm an ice cream shop on a hot summer day, each demanding an ice cream sundae. One sundae requires 50 mL of chocolate syrup, 2 scoops (1 cup) of vanilla ice cream, and 1 cherry. If the shop owner has 600 mL syrup, 25 cups of ice cream, and 20 cherries, how many complete sundaes will he be able to make?" After the basic "how much/how many" problems, I move on to incorporating the mass of "reactants". A fun and (understandably) popular activity then is the S'more lab, attached here. The students 1) measure the mass of a single marshmallow, piece of chocolate, and graham cracker, 2) note the total mass provided in a whole package, 3) determine which ingredient will run out first (the limiting reactant), and 4) calculate how many complete s'mores could be made if they started with a whole package of each ingredient. Oh, and lastly, of course, they get to make s'mores using the Bunsen burners! I require them to answer all of the questions on the activity sheet before they can make a s'more.

Attachments

Smore_stoichiometry.doc (0.04 Mb)

Hi all, Stoichiometry is also one of my favorite topics in Chemistry although just like Francesca, my students will disagree too. When introducing Stoichiometry, I have been relating it to food and my example has always been making a turkey sandwich. I start with simple quantities in making one turkey sandwich and that is, “ 2 pieces of bread + 1 piece turkey --> 1 turkey sandwich”. Then I ask students to make a specific amount of turkey sandwich, given a certain amount of bread and turkey. After that I connect the bread and turkey to reactants and the turkey sandwich to products. This has helped me introduced Stoichiometry to my students but I would like to try other ways of introducing it to them this year. I like to try the Learning Stoichiometry with Hamburger Sandwiches and/or S’more Stoichiometry. I am also interested on the empirical formula activity mentioned in this thread. Any activities and ideas will be helpful to me and my students. Thank you again for all these great ideas and activities.

I like this post because I think it is a chance to link the math and science. I guess it is the same struggle most teachers have with regards to motivating students. Maybe if a real world example that the students can directly relate to may help. Maybe you can find out what they can relate to and then try to hook them into the lesson.

Ruth, I love the cookie idea! I am going to have to "steal" that one (: I usually do "feed the team", but I like your formal lab much better. THANK YOU

Thanks, Angela. Steal away! They were great labs that I borrowed from someone else as well. One of my methods professors said many, many years ago that we should borrow from the best and get rid of all the rest.

Ruth, I see that that is for 4 dozen cookies...do you have each group make that many...or could you modify it and say instead of 4 dozen, make 4 and have them reduce it down??

Chris wrote, 'I see that that is for 4 dozen cookies...do you have each group make that many...or could you modify it and say instead of 4 dozen, make 4 and have them reduce it down??'

Hi Chris,
That is completely up to you and your budget. You could have each group make 4 dozen or you can have them make a portion of the recipe. Normally, I have my class make their conversions for the original recipe and then I have them make a shopping list. Then we decide if they want to make 16 or 20 dozen cookies (depending on the size of the class...if I have four lab groups or five lab groups). Invariably, they decide it would be best that we only make four dozen cookies per class so they divide their original recipe by 4 or 5
depending on how many lab groups that particular section of chemistry has.

One thing I am working on for next school year is working with the FACS teacher to make candy with my chemistry classes and hopefully, her foods and nutrition class. She generally is willing to go along with my crazy ideas. If our scheduling works out, we will do it in the month of December.

We just don't have a FACS program at my school...i don't even think there is an oven on campus...but I was thinking possibly toaster ovens would work :)

Yes, Chris, toaster ovens would work well. Just make sure you don't have too many on the same breaker. You can reduce the recipe by whatever scale you need. If you do this lab, make sure you have a discussion about cost of the lab. For example, most students don't know how much 100 grams of strontium chloride is. However, many students do know the price of a pound of butter. You can also discuss the limitations of your equipment. For example, we couldn't use a full size oven. Instead, we used toaster ovens. That's why each of you only made 1/2 dozen cookies or 1 dozen cookies. It also would be a great lesson to help the students understand why so many chemistry labs are done in microscale.

I'm just curious as I'm entering my Stoich unit next week and am scared of the kids response. what is your general progression as you go through the unit??

Wow! Thanks everyone for all the great ideas! As well as everyone else, I love stoichiometry, but the math skills of my students are pretty minimal. I am starting stoich in a couple weeks and I can't wait to try some of the new ideas you have put up here! Thanks so much! How long do you guys normally spend on stoich? And what are everyone's thoughts on the importance of having students solve limiting reactants problems? Sometimes I think it is a battle not worth fighting!

I have been doing stoichiometry for 2 weeks now. I'm starting limiting reagents tomorrow (i'm pretty afraid of it) and am having a test next Thursday to get it in before we go on spring break. One thing that I did with this that I found to be really helpful to the students was flow maps. My district is pushing the use of Thinking Maps as we transition into common core. I had the students create a flow map of one of the 5 main types of stoichiometry problems. They were put into groups and each group was assigned one of the 5. They were then put into groups of 5, where each member had a different problem type and they created a multi-flow map that they use on homework and quizzes. I think it really helped the kids who took it seriously and used their flow map to their advantage. The main guidance I gave them was to realize that the mole ratio is the central link in all the problems. Here are a couple examples.

Attachments

FlowMap_1.pdf (0.19 Mb)

Apparently you can only do 1 at a time :)

Attachments

Flow_map_2.pdf (0.18 Mb)

Hello Sung Yi! The way you can teach your students is by have them sit in teams and have them race with each other to see what team can come up with the baster answer or who took notes from the chapter and the team that wins can get a home work pass free B or that thable that wins can get a ice crame on you.

Stoichiometry is one of the challenging topics to teach and learn. I though about this topic and looked over the activities provided through the forum, I really like the flow chart map. I think the chart would work because a lot of students don't really understand or visualize how to get from point A to point B. Another think about this topic is that there is a lot of math involved,which can be intimidating for a majority of my students. Let you know on the update.

You could do an aspirin synthesis if you have the class time. It is something they are familiar with. It is also a good way to introduce percent error.

Has anyone here tried using the PhEt animation http://phet.colorado.edu/en/simulation/balancing-chemical-equations

I love teaching my stoichiometry unit! I take my time and don't rush through it at all. I love using the phet Colorado site! I have used the balancing one many times and my students love it. I have them screen shot their scores. They really enjoy playing with the simulation, and it seems to really help them understand balancing.

Great post with a lot of valuable resources I was able to add to my teaching library!

How do you traditionally start your stoichiometry unit?

Here is a CSI and technology application scenarios word document on Stoichiometry I found online a while back. My students love it :) hope it helps. http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved=0CEYQFjAE&url=http%3A%2F%2Fmysite.cherokee.k12.ga.us%2Fpersonal%2Fkatie_freeman%2Fsite%2FChap%252011%2F1%2FStoichiometry%2520Stumpers%2520%28Just%2520for%2520fun%29.doc&ei=6a3UUvDkCfC1sATv_YDYDw&usg=AFQjCNELqDjUUvS0yhZDQTba57f8pF2lQA&bvm=bv.59378465,d.cWc

Attachments

Stoichiometry_Stumpers_(Just_for_fun).docx (0.02 Mb)

:)awesome ideas!!

Most colleagues have mentioned cookies and stoichiometry. A ready made lesson plan can be found on the AACT WEBSITE under High School Lesson plans. This year, I took it a step further and had a collaborative lesson with our Nutrition instructor and it turned out great for both subjects. We plan on doing this again next year.

I know the original post was made some time ago, but once students have a general idea of stoich one of my favorite activities is stoich relay races. My stipulation is that the person at the board is only allowed to write one thing down and then they have to pass the marker. I section off my whiteboards so each team has their own section and make groups up very carefully so that high students can help low students. I am usually VERY picky about their work (right units/sig figs etc.) and if they have something incorrect I don't tell them where it is, just that there is something not right so they all have to go back over their work to find the problem. Even the students that don't like stoich seem to like this activity. I will usually offer hw passes or something similar to winning teams.