I have water pH 7.0 insulation with various other things that do not affect pH, I am trying to add X amount of HCL to lower the solution to a pH of 1.5

Question

I have water pH 7.0 insulation with various other things that do not affect pH, I am trying to add X amount of HCL to lower the solution to a pH of 1.5

I know pH=-log[HCl] but I'm not sure how to approach this problem,
after this I am then trying to add NaOH to return the solution to a pH within the range of 7.0-8.0

Answer 1

I have water pH 7.0 insulation with various other things that do not affect pH, I am trying to add X amount of HCL to lower the solution to a pH of 1.5

How much solution do you have? What is the molarity of the HCl you have?