How many total moles of ions are released when the following sample dissolves completely in water?

Question

31.3 g of Ba(OH)2 · 8H2O

Answer 1

moles Ba(OH)2.8H2O = grams/molar mass = 31.3/315.467 = 0.0992
So you have 1 mols Ba^2+ for every 1 mol Ba(OH)2.8H2O; therefore you must have 0.0992 mols Ba^2+. Following up you will have
2 x that for OH^- ions. In addition you will have an adidtional 8 x that for H2O molecules. I assume you're not counting the small amount of H^+ and OH^- that come from the ionization of the H2O molecules.