What volume of a 0.179 M barium hydroxide solution is required to neutralize 25.6 mL of a 0.377 M perchloric acid solution?

Answer 1

2HClO4 + Ba(OH)2 ==> Ba(ClO4)2 + 2H2O

mols HClO4 = M x L = ?
mols Ba(OH)2 = 1/2 mols HClO4 (from the coefficients in the balanced equation)
Then mols Ba(OH)2 = M x L. You know mols and M, solve for L.