Bell Ringer How does surface area affect a chemical reaction? Today’s Goal I can apply my knowledge of chemical reaction to the real world experience of making fudge. I can identify endothermic and exothermic reactions in real world situations. Begin Reactants • 3 cups sugar • 1 ½ sticks of country crock butter • 2/3 cup of cream • 1 (7 oz.) jar of marshmallow crème • 1 (12 oz. package) of __________ chips. • Energy Recall that activation energy is minimum amount of energy needed to start a reaction. The energy for today’s experiment will come from the hot plate. 1. Explain how the energy gets from the electrical outlet to the pan to heat the reactants. Next In a pan Mix the first 3 ingredients (reactants) until they dissolve into one (compound) This will happen as the heat goes into the pan (endothermic) Look Once they mix together to form a compound OBSERVE the color of the compound. Record a description of your observation. At this point we observe for the mixture to begin to boil. The mixture must absorb enough energy to come to a rolling boil. (It cannot be stirred down) OBSERVE Record observation. Now we begin to time. Time for 6 min. Then we will look at the color of the compound. Next Time’s UP We remove the compound from the energy. Add the (inhibitor) chips, and marshmallow crème. Mix thoroughly and immediately pour in the pan. This is where the exothermic part of the reaction is taking place. Feel the heat being released. Let the majority of the heat be released. When the fudge is cool we can eat it. While you are waiting! Assignment Write up this experiment. Analysis • Explain in detail how making fudge is indeed a chemical reaction. • Use the vocabulary words. (page 514) or your homework (the vocabulary model) • The analysis must use science vocabulary correctly. • Terms to include: endothermic, exothermic, reaction rate factors, reactants, products, evidence of a chemical change • Be specific! Begin now while you wait to eat your experiment. • Analysis is due tomorrow. You may use your notes, book, etc…