We burned a cheezies (2g) under a test tube and the heat combustion was funneled to heat up the water in the test tube.
Here are the data:
water : 15 ml = 15 g
temperature : from 20 to 28 C = a delta of 8 Celsius
Heat transferred to the water = mcT = (15g)(4.19 j/gC)(8C) = 503 J = 0.503 kJ
Heat coming from the cheezies = 0.503kJ = 0.503kJ/4.18kJ/Cal = 0.12 Calories
25 cheesies = 25(0.12 Cal) = 3 Cal
The bag says 300 Cal (25 cheezies)
Can someone explain why I am so off. Experimentally, I found 3 Cal instead of 300 Cal, a factor of 100.