Question

A solution is prepared using 15.0 mL of 1.0 M HCl and 20.0 mL of 0.5 M HNO3. The final volume of the solution is 1.25 L. What are the [H3O+] and [OH-] in the final solution? What is the pH of the final solution?
Ok. I got 0.015 mol HCl and 0.1 mol HNO3. Do I just add the moles to get the total? So 0.115 total moles. Which would make a the Molarity of the final solution 0.092M?

Answer 1

add the moles, in reality you are adding the H+ concentrations.

It is the concentration of H+ which determines pH

Answer 2

ok thankyou!

Answer 3

for what works the 1.25L that they give you in the problem?

Answer 4

never mind, just figure it out