LearnChemE

Energy Balances with Reaction: ConcepTest and Example Problem

Try to answer this ConcepTest and solve the example problem before using this module. Studies show that trying to answer the questions before studying material improves learning and retention. We suggest that you write down the reasons for your answers. By the end of this module, you should be able to answer these on your own. Answers will be given at the end of this module.

Image of a concepTest for the Energy Balances with Reaction module on LearnChemE.com
Example Problem 1

100 mol/h of N2 and 300 mol/h of H2 are fed to an isothermal reactor at 350°C to carry out the following gas-phase reaction:

N2 + 3H2 → 2NH3

Assume the heat capacities for the components are the following:

Cp(N2) = Cp(H2) = 29 J/mol-K

Cp(NH3) = 36 J/mol-K

How much heat must be removed from the reactor if the conversion is 75%? The heat of formation of ammonia at 25°C is -46 kJ/mol.