a) A 40 mL of a %10 aqueous KOH solution (density:1.12 g/mL) is mixed with 210 mL of 0.25 M HNO3. Then 5.22 g of solid K2SO4 added into this solution (Assume that the addition of solid K2SO4 does not change the total volume (300 mL) of the final solution). Calculate pH of this solution using activity? H3O+ = 0.9 nm, OH-= 0.35 nm

b) Calculate the pH of the 1x10-8 M Sr(OH)2 solution. Sr(OH)2 is a strong base and it completely dissociates into its aqueous solution.