Example: 1.40 g of vegetable oil is placed in a bomb calorimeter with excess oxygen and ignited with a spark. If the calorimeter temperature changes from 20.000 °C to 21.195 °C, find the energy released per gram of oil . The calorimeter contains 2.50 kg of water. The calorimeter without water has a heat capacity of 1.00 kJ°C-1.

q = nCpDeltaT, where Cp is the molar heat capacity at constant pressure (= 75.3 J C-1mol-1 for water).

q= qwater + qcalorimeter

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hess's Law

some properties of enthalpy

 

 

 

 

Standard States:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

EM_Spectra_image

public domain image from Louis E. Keiner via Wikipedia Creative Commons

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

sine wave diagram

public domain image via Wikipedia Creative Commons

 

 

 

 

 

 

 

 

sine wave animation

public domain image via Wikipedia Creative Commons

 

 

 

 

 

 

 

 

EM_Spectra_NASA_image

public domain image from NASA via Wikipedia Creative Commons

© R A Paselk

Last modified 4 March 2011