A solution of a nonvolatile solute in water freezes at -0.30^oC. The vapour pressure of pure water at 298 K s 23.51 mm Hg and K_f for water is 1.86 K kg mol^-1. Calculate the vapour pressure of this solution at 298 K.

Calculate the equilibrium constant for the reaction:
2Fe³⁺ + 3I^- $$\leftrightharpoons$$ 2Fe²⁺ + $$I_3^-$$. The standard reduction potentials in acidic conditions are 0.78 V and 0.54 V respectively for Fe³⁺ | Fe²⁺ and $$I_3^-$$ | I^- couples.

Find the solubility product of a saturated solution of Ag₂CrO₄ in water at 298 K if the emf of the cell Ag|Ag⁺ (satd. Ag₂CrO₄ soln.) || Ag⁺ (0.1 M) | Ag is 0.164 V at 298 K.

The rate constant of a reaction is 1.5 $$\times$$ 10⁷ s^-1 at 50^oC and 4.5 $$\times$$ 10⁷ s^-1 at 100^oC. Evaluate the Arrhenius parameters A and E_a.