18. Aqueous Equilibrium

What will be the color of the indicator in the above question in a solution that has a pH of 6?

Consider the titration of 60.0 mL of 0.200 M H₃PO₃ solution with 0.350 M potassium hydroxide, KOH solution. How many milliliters of base would be required to reach each of its equivalence points? 

Chlorous acid: pK_a = 1.95
Nitrous acid: pK_a = 3.34
Formic acid: pK_a = 3.74
Acetic acid: pK_a = 4.74
Hypochlorous acid: pK_a = 7.54

Consider the titration of 100.0 mL of 0.40 M HCl with 0.40 M NaOH. If sodium hydroxide is the titrant, which volume would place it in excess? 

a) 70.0 mL                    b) 25.0 mL                    c) 100.0 mL                   d) 110.0 mL                   e) 9.0 mL