“This week, the 11th Grade IB Chemistry students performed an experiment on S’mores, through which we learned about stoichiometric concepts such as limiting and excess reactants. In the experiment, we distributed equally the materials among three groups. The materials consisted of Graham crackers, big marshmallows, small marshmallows, and dark chocolate bricks. Each group received twelve Graham cracker pieces, six chocolate blocks, eleven small marshmallows and nine big marshmallows. My partner and I made our S’mores such that each S’more had two Graham crackers, two chocolate pieces, one big marshmallow, and one small marshmallow. By the end of our preparations, we had an excess of big and small marshmallows because they were not entirely consumed. Our limiting reactants were the Graham crackers and the dark chocolate pieces because at the end of making S’mores there were none left as they were all used in making our six S’mores. Through this experiment, we learned about the law of conservation where the mass of the product is equal to the sum of the masses of reactants. We observed this in our S’mores experiment, thus learning that there, in fact, is a relationship between the mass of a S’more and the masses of the reactants.”
“Last Tuesday, we were told to make s’mores as introduction to our lesson on stoichiometry and limiting and excess reagents in chemistry. After dividing the marshmallows, graham crackers, and pieces of chocolate amongst 3 groups, we found out that there was an excess of marshmallows. In total, we created 6 s’mores with 2 marshmallows, 1 block of chocolate, and 2 graham crackers each. Because we completely used up the graham crackers and chocolate making only 6 s’mores, those two ingredients were our limiting reagents. The marshmallows, on the other hand, was our excess reagent as there were still extra marshmallows after the activity.
This activity was entertaining, highly educational, and an interactive way to learn about chemistry. It allowed me to gain a deeper understanding on excess and limiting reagents whilst having an enjoyable time making and eating s’mores.”
“Previously this week, we made s’mores in class. However, the purpose of these s’mores wasn’t just to serve as a delicious snack during the day, but an equally delicious lesson about stoichiometry. Using the ingredients as substitutes for different elements, we were able to identify and define limiting reagents using a practical and delicious method. By crafting the s’mores, we were able to discover that a limiting reagent is the material responsible for a reaction reaching completion. With s’mores, the limiting reagent was the graham crackers and the marshmallows. As a result, what was left over were the marshmallows. Even if they were left over, we later put them to good use by creating a makeshift s’mores dip! It was a delicious lesson, and to quote Ms. Cherry Tan, it was “stoichi-yum-etry!”
“Yesterday in chem class our teacher told us to bring marshmallows, graham crackers, and chocolate to make S’mores!!!!!!. We were split into groups and we were free to use the ingredients to make as much s’mores as we can. My group had 9 graham crackers, 12+ marshmallows, and 12 chocolates. We were able to only create 6 s’mores with two marshmallow, 2 graham crackers and 2 chocolates for each s’mores. The ingredient that ran out were the graham crackers and the chocolates, therefore they were the limiting reactant. The marshmallows were the excess reactant.”
“The s’mores activity was very educational because it visually represents our topic, stoichiometry. It demonstrates what an excess reagent is and also what a limiting reagent. In this case, the excess reagent were the marshmallows while the limiting reagent were the graham crackers and chocolate bars. The limiting reagent (chocolate and graham crackers) limited us to making only 6 s’mores.”
2 graham crackers + 2 marshmallows + 1 chocolate brick = 1 s’mores
12 graham crackers + 12 marshmallows + 6 chocolate bricks = 6 s’mores
The maximum number of S’mores that we were able to craft from our ingredients of 12 graham crackers, 23 marshmallows, and 12 chocolate pieces. The supply of graham crackers and chocolates were used up first, leaving an excess of 13 marshmallows. This way they are the crackers and chocolate act as the limiting reagents whilst the marshmallow as excess reagent. Our group was able to make 6 S’mores in total, having each one encompass of two marshmallows (one mini and large) and 2 chocolate bricks and top-bottom coverage of two graham crackers.
This “sweet” experiment was designed to mimic the synthesis of a compound and better understand the concept of reactants and products through the use of food. I found it fascinating how the concept of Stoichiometry can applied in mundane activities such as making s’mores. Overall, the experiment not only allowed us to understand the concept of limiting and excess reagents more thoroughly through physical perceivement but also enjoy the sweet treat of warm s’mores ”