209) Vapourisation 1 mol of PCl₅ is done in a 1 L container. If 0.2 mol of Cl₂ is formed at equilibrium, then what will be the value of equilibrium constant?

210) The vapour density of N₂O₄ at a certain temperature is 30. Calculate the percentage dissociation of N₂O₄ at this temperature:

211) The equilibrium constant for mutarotation of α−D glucose to β−D glucose is 1.8. What percent of the α−form remains under equilibrium?

212) When sulphur is in the form of S₈ is heated at 900 K, the initial pressure of 1 atm falls by 29% at equilibrium. This is because of conversion of some S₈ to S₂. Find the value of equilibrium constant for this reaction:

213) What is the approximate OH⁻ ion concentration of a 0.15M NH₃ solution? (K_a = 1.75 x 10⁻⁵)