pH of HCl solution as a function of volume.

Bipolarity

1. The problem statement, all variables and given/known data
You have a 1L of a 2M HCl solution. Assume that the HCl completely ionizes.
a) Calculate the pH of the solution right now.
b) You now add V litres of water to the solution.
Find the pH of the new dilute solution in terms of V.


2. Relevant equations
pH = -log[H]


3. The attempt at a solution
a) pH = -log(2) which is interestingly a negative number so I hope this is correct.
b) I'm not sure how you would do this part. Do we just find the new concentration in terms of V and then find the negative log of that? Don't we have to consider the autoionization of water?

Thanks!

BiP

Borek

Yes, negative pH is possible.

Check the link I posted in your other thread for the way pH should be calculated. And read about dilution calculation.