I'm having trouble understanding why the fact that there are two hydroxides doesn't matter in this problem. What volume of 0.150-molar HCl is required to neutralize 25.0 milliliters of 0.120-molar Ba(OH)2? I thought the setup would look like this simple enough: (25.0 mL)(.120 M)(2) = (.150 M)(V) and the volume came out to be 40.0 mL. I assumed that the neutralization reaction looked like this: 2HCl + Ba(OH)2 --> 2H2O + BaCl2 so for each mole of Ba(OH)2 there would be two moles of HCl. However, I was told the answer was 20.0 mL. Why is the presence of two hydroxides negligible, or is the answer I was given incorrect?