Determine the units of the K. and Kp for the following reactions:

(i) H₂(g) + I₂(g) ⇔ 2HI(g)

(ii) CH₄(g) + H₂O(g) ⇔ CO(g) + 3H₂(g)

(iii) PCl₅(g) ⇔ PCl₃(g) + Cl₂(g)

What is Le Chatelier's principle? Explain with the help of Le Chatelier's principle, the effect of temperature and pressure on the reaction:

2SO₂(g) + O₂(g) ⇔ 2SO₃(g)    ΔH°= -196.6 KJ

Write down the integrated rate equations of second order reaction. Show that, half-life of a second order reaction is depending on initial concentration of reactant.