Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Question check calorie question

  1. Apr 13, 2006 #1
    Explain the laboratory methods used to determine the energy content of foods?
    The laboratory methods used to determine the energy content of foods would be to combust it in a bomb calorimeter. Let’s say that I wanted to see how much calories is in a peanut. What I would do is burn it in a bomb calorimeter. As I am burning it, I would record the temperature of the water inside the bomb calorimeter. After the peanut is completely burned, I would calculate the Q value of water. Let's the temperature changed 6.0 oC and the mass of water was 100.0g. I calculate Q by (6.0 oC)(100.0g)(4.18kJ/ oC), which is 2508J. I would divide that with 4.184J because 1cal=4.184J. The calories in that peanut would be 599.43 cal.
  2. jcsd
  3. Apr 13, 2006 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Looks right to me. Just take care on your units, the units of specific heat are KJ/ (kg K) don't forget the mass unit.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook