What is the molarity of an hcl solution if 27.3 ml of it neutralizes 134.5 ml of 0.0165 m ba(oh)2?

Hey there!:

2 HCl + Ba(OH)2 = BaCl2 + 2 H2O

Moles Ba(OH)2 = 0.1345L*0.0165M=0.002219 moles

Moles OH= 2*moles Ba(OH)2= 0.004438 moles

It are required the same amount of hydrogen moles to neutralizes the solution so  ;

Moles H=0.004438, and the same amount of moles HCl= 0.004438 moles divided by the volume

M=0.004438 /0.0273= 0.163 M

Hope that helps!