Essentially, we bu rn food inside our bodies when we digest it. We use enzymes (Chapter 13) so that we can burn the food at temperatures safe to be inside of us. For this lab we are going to experimentally determine how many Calories we would gain for every gram of cashew nut that we eat. This is a very crude experiment and a lot of heat is lost. That is why the numbers that we get will be lower than 6 Cal I g, the typical value that you will find on a bag of nuts. Experimental Setup 1 In the image to the left there is a cashew on fire. The nut is being held up by a paperclip to help minimize heat loss. Above the fire is an aluminum can with water and a thermometer in it. It takes 1 calorie (not a food Calorie) to heat 1 gram of ICE: 0 water by 1 C, g*C' Using conservation of energy, we know that all of the energy that heated the water had to come from the cashew. Set 2) Determine how many grams of cashew was burned. Determine Cal / g of cashew. Step 1) Determine how many Calories was burned. Specific Heat (C) Before burning After burning C = 1 cal m.AT g.AT 2.00 , Rearranged to solve for heat (q) 1.17, q = C . g . AT Determine how many grams of water was added. A nifty trick is to "zero" the scale before you start. make sure to fill in Water Empty with Mass (water) DEIONIZED WATER water Before After Change Temperature 168.89 (AT calories gained by water Determine how many C the water was heated by. The numbers shown are 10, 20, 30... C. q = C . g . AT Cashew Before After | Change Mass (cashew) calories / gram Calories / gram 1000 cal = Cal Before heating After heating