4. Answer the following questions using the below titration curve for H3PO4 (a triprotic acid). The titrant being added to the acid is NaOH. 14 Hd 12 10 00 6 4 2 0 0 0.5 1.5 Equivalents OH B) What is the approximate pKa value of HPO4²-? 2 A) Label all of the approximate pka points on the above curve. C) What is the dominant species of the titration mixture at pH = 4.5? 2.5 3

The Ka of HCIO is 3.0x 10-7. When titrating a 50 mL solution of 1 M HCIO with 0.25 M KOH, what will the pH be when you've added 100 mL of the KOH solution? Hint: what point on the titration curve is this?

Which indicators that would be suitable for each of the following titrations: HNO3 with NaOH thymol blue    bromophenol blue    methyl orange    methyl red    chlorophenol blue    bromothymol blue    cresol red    phenolphthalei

12:04 Question 4 of 9 Submit A buffer solution contains dissolved C6H5NH2 and C6H;NH;CI. The initial concentration of C6HŞNH2 is 0.50 M and the pH of the buffer is 4.20. Determine the concentration of C6HŞNH3* in the solution. The value of Kb for C6H;NH2 is 3.8 × 10-1º. 1 2 3 Let x represent the original concentration of C6H,NH,* in the water. Based on the given values, set up the ICE table in order to determine the unknown. C6H5NH2(at H20(1) = OH-(aq) +C6H5NH3*(a Initial (M) Change (M) Equilibrium (M) 5 RESET 0.50 - 4.20 -4.20 6.3 x 10-5 -6.3 x 10-5 1.6 x 10-10 -1.6 x 10-10 3.8 x 10-10 -3.8 x 10-10 x + 4.20 x - 4.20 x + 6.3 x 10-5 х - 6.3 х 10-6 x + 1.6 x 10-10 x - 1.6 x 10-10 x + 3.8 x 10-10 x - 3.8 x 10-10 Tap here or pull up for additional resources