J.R. S. answered 10/08/19
Ph.D. University Professor with 10+ years Tutoring Experience
Balanced equation:
Ba(OH)2 + 2HCl ==> H2O + BaCl2
First, find MOLES HCl present:
14.8 ml x 1L/1000 ml x 0.274 moles/L = 0.004055 moles HCl
Next, using the stoichiometry of the balanced eq. (1Ba(OH)2 : 2 HCl), find moles Ba(OH)2 needed:
0.004055 moles HCl x 1 mol Ba(OH)2/2 moles HCl = 0.002028 moles Ba(OH)2
Finally, calculate volume of 6.83x10-2 M Ba(OH)2 needed to provide 0.002038 moles:
(x L)(6.83x10-2 mol/L) = 0.002038 moles
x = 0.02969 L = 29.7 mls (to 3 significant figures)