Haber+Process

= The Haber Process =

Basics

Equilibrium

Since the Haber Process is an exothermic reaction, increasing the temperature causes a shift towards the left. This causes an increase in the amount of reactants. Hence, a decrease in temperature shifts the equilibrium to the right, increasing the quantity of products. Additionally, since the moles of reactants is greater than that of products, an increase in pressure in the environment of the reaction would lead to an increase in products. Source-http://www.chm.davidson.edu/vce/ChemEquilibria/HaberProcess.html & http://en.wikipedia.org/wiki/Haber_process#Reaction_rate_and_equilibriumSince the Haber Process is an exothermic reaction, increasing the temperature causes a shift towards the left. This causes an increase in the amount of reactants. Hence, a decrease in temperature shifts the equilibrium to the right, increasing the quantity of products.

Catalyst

The catalyst used in the Haber process is a porous iron based catalyst which contains potassium hydroxide to increase the efficiency of the reaction. In the process the gasses are passed over four beds of catalyst to lower the activation energy.Without the catalyst the process is too slow to produce ammonia on an industrial scale. Source-http://www.chemguide.co.uk/physical/equilibria/haber.html

Practice Question

**IB Paper 2 Question on Haber Process ...** http://ibchem.com/IB/ibnotes/full/equ_htm/8.2.htm For the Haber Process equilibrium **N2 + 3H2** 2NH3

The equilibrium law gives the expression:
 * **Kc =** ||   **[NH** **3** **]** **2**   ||   ||
 * ^  ||   **[N** **2** **] x [H** **2** **]** **3**   ||^   ||

In one experiment a mixture of H2, N2 and NH3 was allowed to reach equilibrium at 472°C. The concentration of gases at equilibrium was analyzed and found to contain the following:

What value did Haber come up with for the equilibrium constant, Kc?
 * component ||  concentration  ||
 * hydrogen ||  0.1207M  ||
 * nitrogen ||  0.0402M  ||
 * ammonia ||  0.00272M  ||