7. Calculate the pHi of a 0.25mM KOH solution. (2 pts) 8. What is the [H*] in molar, millimolar, and micromolar for a solution of pH5 ? (3 pts) 9. If you mix 100mL of a 0.1MHCl solution with 30mL of a 250mMCa(OH)2 solution, what is the resulting pH ? (4 pts) 10. If you mix 60mL of 0.2M acetic acid with 80mL of 0.4M acetate, what is the resulting pH? (3pts) 11. How many total milliliters of 1MNaOH can you add to the solution in Question #10 and still have a good buffer (that is, within 1pH unit of pK4) ? (4 pts) 12. If you are making 100mL of a 0.1M HEPES buffer starting from HEPES in the basic form, is it prudent to get 50mL of 1MHCl from the community reagent bottle to use for your titration? Why or why not? (2pts)