Answer
a) Equilibrium will not be affected
b) Shift left
c) Shift right
Work Step by Step
a) When additional UO_{2} is added to the system, the equilibrium will not be affected since the equilibrium position is independent of the pure solid or liquids present. Pure solids or liquids cannot impact the equilibrium position because the concentration of these substances cannot change. Since UO_{2} is solid, the equilibrium will not shift here.
b) HF(g) reacts with the glass vessel, which removes HF(g) from the system, therefore the system will shift to replace the lost HF.
c) Removing a gaseous product (H2O) causes the system to shift to produce more product, hence the equilibrium shifts right to replace the lost H2O.
