Energy Balances with Reaction: Summary

The answers to the ConcepTests are given below and will open in a separate window. 
Key points from this module:
  1. The equation relating initial pressure and temperature to final temperature and pressure for an adiabatic reversible process for an ideal gas is the same for a closed system and for a steady-state flow system.
  2. When an ideal gas is compressed adiabatically, its temperature increases.
  3. When an ideal gas is expanded adiabatically, its temperature decreases.
From studying this module, you should now be able to:
  • Reference states for enthalpies need to be clearly specified in an energy balance.
  • An energy balance for a reactor can contain a heat of reaction term explicitly or heats of formation can be incorporated into individual enthalpies.
  • An inert, even though not involved in a reaction, can affect the outlet temperature or the amount of heat added or removed.
Look at the Adiabatic Flame Temperature module after completing the current module.

Prepared by John L. Falconer, Department of Chemical and Biological Engineering, University of Colorado Boulder