Cheeto Calorimetry
The magnitude of heat given off by a burning Cheeto is used to measure approximate caloric content of a Cheeto.
Measure the mass of a Cheeto prior to doing the demonstration. Ignite the Cheeto and quickly place the burning Cheeto underneath a beaker containing 50.0 mL of water. The burning Cheeto heats the water. The initial and final temperature of the water is measured and recorded. Temperature rise is monitored. The change in temperature is calculated. Measure the mass of the Cheeto after it has burned.
The heat gained by the water is calculated,
q gained by water = mass of the water x specific heat of the water x ΔT.
The heat given off by the Cheeto is calculated q loss + g gain = 0
q loss by Cheeto + q gain H2O = 0
Calculate the heat released (in units of Joules) per gram of food that burned
Heat released per gram = Heat released by the Cheeto (J)/mass of Cheeto that burned (grams)
Determine the Food Calories in one Cheeto and compare this to the Label on a Bag of Cheetos.
How many Calories per serving?
The URL for a good video of this demonstration: https://vimeo.com/167310239
The URL for a not so good vidoe of this demonstration:
https://www.youtube.com/watch?v=UDgeaAMdYIY
Make a list of all of the safety violations.
This demo serves as a good introduction to thermochemistry in the "Introduction to Chemistry" course - or a good closing demonstration for thermochemistry in the General Chemistry I course. Particularly the following concepts are illustrated: heat loss + heat gain = 0; All foods contain chemical compounds, when food burns it releases energy (heat and light) due to bonds breaking and bonds forming; chemical bonds contain stored energy (potential energy), a calorimetry experiment can be run to determine the amount of calories in food; 1.00 Food Calorie = 1,000 science calories; combustion reactions generate heat.
On ring stand there will be two clamps. On the bottom clamp use the buret clamp to hold the 50ml beaker. On the top clamp use the three fingered clamp to hold the Vernier stainless steel thermometer probe that is connected to the GoLink! interface. This plugs into the usb port of computer with appropriate Vernier software. Place watch glass under beaker to catch ashes.t
- Vernier stainless steel thermometer probe and a GoLink! interface
- Bag of Cheetos
- Computer with Vernier with Logger software (dongle if using mac)
- RGB cable
- Lighter
- Forceps
- Large watch glass
- Ring stand and two ring stand clamps
- Small 3 fingered clamp
- Buret clamp
- 50 ml beaker
- Small bottle of DI water
Load logger software and expand the temperature reading to fit the full screen. Use forceps to hold Cheeto and light on fire. Hold burning Cheeto under the 50 mL beaker and monitor the increase in temperature.
| Mass of Water | Intitial Temperature | Final Temperature | Change in Temperature |
Since fire is involved keep paper and other flammable materials clear of demo space. Make sure that the watch glass is placed under the burning Cheeto to catch falling pieces.
