Answer
(a) $I_2$ would be favored. The equilibrium will shift to the right.
(b) $I$ would be favored. The equilibrium shifts to the left.
(c) It depends. If this is an exothermic reaction, the equilibrium will shift to the left, if it is endothermic, will shift to the right.
As we know, reactions where bonds are forming (I - I) are likely to be exothermic , so the equilibrium will probably shift to the right.
Work Step by Step
(a) If there are gases in both sides of the reaction, the one with the least amount of moles of gases will be favored after increasing the pressure.
(b) Adding more product favors the reverse reaction, shifting to the left.
(c) Explained above.
