Factors affecting equilibrium: Le Chatelier’s principle - Change of Concentration

Does the number of moles of reaction products increase, decrease or remain same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?

\[\ce{PCl5 (g) ⇌ PCl3 (g) + Cl2 (g)}\]

Does the number of moles of reaction products increase, decrease or remain same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?

\[\ce{CaO (s) + CO2 (g) ⇌ CaCO3 (s)}\]

Which of the following statements is incorrect?

The pH of neutral water at 25°C is 7.0. As the temperature increases, ionisation of water increases, however, the concentration of \[\ce{H+}\] ions and \[\ce{OH-}\] ions are equal. What will be the pH of pure water at 60°C?

On the basis of Le Chatelier principle explain how temperature and pressure can be adjusted to increase the yield of ammonia in the following reaction.

\[\ce{N2 (g) + 3H2 (g) ⇌ 2NH3 (g) ∆H = - 92.38 kJ mol^{-1}}\]

What will be the effect of addition of argon to the above reaction mixture at constant volume?