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1. How much H_2SO_4 would you need to make a solution with a pH of 5?
2. What is the pH of a solution that contains 4.53 grams of NaOH in 2.85 liters of solution?
3. What is the pH of a solution that contains 0.00372 moles HCI in 2.39 x 10^-2 liters of solution?
1. meaningless. You need to specify a quantity of water.
The pH is the ratio of particles. A mole contains 6.023 x 10^23 particles, so the concentration is simply the ratio of moles. Well, actually the negative log of the ratio. You should know how to figure moles, since this subject is meaningless without that ability.
These problems are easy because you are given a strong acid and a strong base. Strong acid or base means it ionizes completely in water. It has nothing to do with concentration or corrosiveness. There are seven strong acids:
Sulfuric
Nitric
Hydrochloric
Chloric
Perchloric
Hydrobromic
Hydroiodic
It's easy to remember the list because there are three of the most common industrial acids, three "chloric" acids, three "hydro" acids, and they all make a clumsy "7" on the periodic table.
There are dozens of strong bases and hundreds of "almost strong" bases.
