Give Me S’more Chemistry! Standard SC2.c How can making S’mores help us to understand Stoichiometric relationships?

Not a Perfect Analogy Putting together a S’more is not a chemical reaction. You cannot see atoms/molecules like you can see S’more ingredients. Quantities (moles in particular) are much larger in chemistry. Hard to replicate the true mole because of the size of the number. (6.02 x is a LOT!)

So Why Are We Doing This? Strengthen your use of Dimensional Analysis before the REAL Stoichiometry. The ratio concept of exchanging moles is easily illustrated with S’more making. You will be able to see how mass of one substance is determined from the mass of another. It’s fun and tastes good!

Ingredients You can make a whole variety of S’mores, but the one we will be dealing with is the traditional. 2 Graham Crackers, one large marshmallow (roasted of course!), and three chocolate pieces from a chocolate bar. On your worksheet, you’ll notice the symbols for each (again, we are trying to mirror a chemical equation as much as possible).

Source of S’more “Elements” We mine these “elements” from various mines… the Kroger Mine, the Publix Mine, and occasionally the Ingles Mine. They usually come in clusters (which we will call “packages”). Tomorrow, when we get to the actual masses of these “elements”, we will show how to put packages together using Stoichiometry.

So What Are We Doing Today? Good Question… we are going to learn the exchange of elements. Later, you’ll see how this is always the second (and easiest) step of the process. So, we’ve got the “equation” and the “elements”… let’s practice a bit before you do some work on your own.

Equation Synthesis of a S’more: 2Gc + 1M + 3Cp  ? What is the ratio of Gc to M? What is the ratio of M to Gc? What is the ratio of Cp to Product? If there are 6 dozen Cp, how many dozen M would be needed? (Use the ratio!)

Practice Questions How many S’mores can be made with 43.2 Gc? If 6 S’mores are made with 30M, How many M would be left over? If you have 40 Gc, 40 M, and 40 Cp and you make as many S’mores as possible, which ingredient will have the most left over?

Now, Complete the Worksheet Use the remaining time to work on the worksheet. I will stamp assignment sheets for those working up until the end of class. If you do not complete the worksheet, do so for homework.