How to predict products of acid-base reactions?

12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer

Chemistry worksheet - i am not sure what they are asking for exactly?

How many moles of sulfuric acid (h2so4) are needed to react completely with 6.8 moles of lithium hydroxide (lioh)? 2lioh + h2so4 → li2so4 + 2h2o a. 3.4 mol h2so4b. 6.8 mol h2so4 c. 10.2 mol h2so4 d. 13.6 mol h2so4