posted by PHD Hopeful .
How will the following system at equilibrium shift in each of the following cases?
2 SO3(g) <--> 2 SO2(g) + O2(g) H° = 197 kJ
(a) SO2(g) is added
(b) the pressure is decreased by increasing the volume of the container
(c) the pressure is increased by adding Ne(g)
(d) the temperature is decreased
(e) O2(g) is removed
Don't you have some ideas about what happens. Remember, Le Chatelier's Principle says that when a system at equilibrium is subjected to a stress, the reaction will shift in such a way so as to relieve the stress.
I'll do the first one.
when SO2 is added (a product) what must the reaction do? It must shift so as to use up the SO2 that was added. How can it do that? It can shift to the left, using up some of the O2 and some of the SO2 and forming more SO3. That way the SO2 concentration (the material which stressed the equilibrium) is reduced. Now you try the others and give reasons.