Answer the following showing all work, equations, units, etc. Be sure to show the chemical reaction for each problem (if available).
1. What is the sulfuric acid, H2SO4, concentration of a solution with pH = 4.21.
2. What is the barium hydroxide concentration of a solution with a pH = 9.35?
3. What is the hydronium ion concentration of a solution with a pH of 12.4?
4. What is the pOH of a 4.23E-2M nitric acid, HNO3, solution?
5. You have calculated the H+ concentration of the sulfuric acid solution in Question 1. This concentration does not include the H+ concentration from the autoionization of water (about 1.0E-7M for [H+] or [OH1-]). Explain why (including some addition and sig figs) we do not usually include this H+ concentration contribution when we calculate pH.
Answer: 1)3.1E-5M 2)1.1E-5M 3)4E-13M 4)pOH=12.626 5) [H+] from acid >>> [H+] from water