[Thought Hammer]

I have already found out that I can titrate and use stoichiometry to verify that the molarity of my prepared(diluted) solution of HCl is close to the target value of .3500M.

However, I am befuddled on how to approach another method (my teacher says that density should be used but I am doubtful on that statement).

If someone has any ideas on any methods, please help. Thanks!

[Borek]

You can measure density and check in density tables (not too accurate), you can use refractometry, you can use pH meter. Plenty of possibilities, but a lot depends on what you have at hand.

[RandoFlyer]

Do you know the molarity of your stock/initial solution? In that case:

C₁V₁ = C₂V₂