Question

Prepare a 0.0200 mM dye solution at low pH by dilution 0.40 ml of the stock 0.100 mM chemical X into the appropriate volume of 2.5 M HCl.

What is the amount of HCL required for dilution, the final concentration of HCl in the solution, and the pH?

I know there's the MV = MV, but I'm not sure how to begin to solve this. The 2.5 M HCl throws me off since there's two concentrations now (2.5 and the .02)

Answer 1

The 2.5 M HCl is the diluting agent and has nothing to do with the calculation for the dye. (Another way of saying it is that the 2.5 M HCl is just water as far as the dye dilution is concerned.). My MV = MV gets 2 mL.

The HCl is 2.5 x (1.6/2.0) = ?? if we assume the volumes are additive.

Answer 2

How were you able to get the 1.6?