Question

Describe how you would make 100 mL of a hydroiodic acid solution that has a PH of 2.5

Answer 1

Just use the fact that pH=-log(H) and this will find your molarity of H+ needed. From there you know you need 100ml so that just .1 L (knowing that molarity=moles per liter). Then you know exactly how many moles H+ are needed and knowing that you are using hydrooiodic acid, you can find an exact mass of this acid that you would add to your 100ml of water.