The volume of HCl = 24.27 ml
Reaction
2HCl + Ba(OH)₂ ⇒ BaCl₂ +2 H₂O
mol of Ba(OH)₂ = V x M
[tex]\tt 35\times 0.52=18.2mlmol[/tex]
From the equation, the mol ratio of HCl : Ba(OH)₂ = 2 : 1, so mol HCl :
[tex]\tt 2\times 18.2=36.4~mlmol[/tex]
So the volume of HCl :
[tex]\tt n=M\times V\\\\V=\dfrac{n}{M}\\\\V=\dfrac{36.4}{1.5}=24.27~ml[/tex]
Or you can use the titration formula :
M₁V₁n₁=M₂V₂n₂(n HCl=1, n Ba(OH)₂=2) :
[tex]\tt 1.5\times V_1\times 1=0.52\times 35\times 2\\\\V_1=24.27~ml[/tex]
