Part One: Calculate the molarity of Ba2+ in an aqueous solution that contains 1.7 g of Ba(OH)2 in 0.75 L of solution. Answer in units of mol/L.

Part Two: What is the molarity of H3O+?
Answer in units of mol/L.

Explanation:

Ba(OH)2 ==>  Ba2+  +  2OH-

1.7 g = 0.008172796 moles Ba(OH)_2

1:1 for Ba2+ = 0.008172796 moles / .15L = 0.054M

2:1 for OH- = 0.016345593 moles / .15L = 0.109M

Kw = [H+] x [OH-] = 10^{-14}

10^{-14} / 0.109 = 9.2×10^{-14}  = [H+]