How much 12 M HCl do you add to 1 L of water to obtain 0.2 HCl? Use this same approach to do the math for the dilution of 5.5 M of barium hydroxide solution to 0.5 M barium hydroxide solution.

Answer 1

Do you mean 0.2 M HCl? I assume so.
Use the dilution formula for both HCl and for Ba(OH)2.
That is c1v1 = c2v2
c = concn
v = volume