Question

What effect (shift to the right or left) does an increase in temperature have on each of the following systems at equilibrium?



a) 3O2(g) ==> 2O3 (g)
<==

Delta H = 284 KJ










b) 2SO3(g) + O2(g) ==> 2SO3(g)
<==
Delta H = -198.2 KJ

Answer 1

When heat is involved, I find it helpful to rewrite the equation with the heat shown; i.e.,
3O2(g) ==> 2O3 (g)
<==

Delta H = 284 KJ
I would rewrite this as
3O2 + heat ==> 2O3. Then adding heat is the same as adding O2. It will shift to the right.

2SO3(g) + O2(g) ==> 2SO3(g)
<==
Delta H = -198.2 KJ
I would rewrite as2SO3 + O2 --< 2SO3 + heat.
Therefore, adding heat will shift the equilibrium to the left.