A mole ratio is simply a ratio of the number of moles of one molecule or atom to another. The purpose of mole ratios is to be able to compare either the amounts of a molecule needed to produce a product or the amount of a product produced with a given amount of molecule. The following is a lab intended to acclimate students to using moles ratios.
Utilizing the law of conservation of mass and principles of stoichiometry, students will build s’mores. A traditional camping snack, a s’more is normally made by putting a roasted marshmallow in between two graham crackers and adding a bar of chocolate at one end. This activity will allow students to get a hands-on grasp of stoichiometry and the concept of limiting reagents. In this activity students will get to decide the composition of their s’mores and eventually they will find that they run out of materials to make them. The first material that they run out of will be the limiting reagent in their experiment. The composition of their s’more will dictate the mole ratios.