Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3 and 0.0012 M H2CO3 (pK, for H2CO3 at body temperature is 6.1). a. What is the pH of blood plasma? b. If the volume of blood in a normal adult is 5.0 L, what mass of HCl can be neutralized by the buffering system in blood before the pH falls below 7.0 (which would result in death)? c. Given the volume from part (b), what mass of NaOH can be neutralized before the pH rises above 7.8?

A 200. mL sample of buffer contains 1.20 M CH3NH2 (methylamine) and 1.00 M CH3NH3Cl (methylammonium chloride). a. Write the net ionic equation that shows how the buffer will react with added generic acid H+. b. Write the net ionic equation that shows how the buffer will react with added generic base OH–. c. Determine the pH of this buffer solution. d. Determine the pH of this solution after the addition of 8.0 mL 5.0 M HBr. e. Phenol red is an organic compound that can be used as an acid/base indicator with pKa = 7.2. The two different forms and colors of phenol red are shown. At the pH you determined in part b, what color would you expect the phenol red indicator to be? (Circle one.) yellow, orange, pink, cannot predict

8. Suppose we titrate 24.0 mL of 0.100M HCIO4, a strong acid, with 0.100M NaOH, a strong base. Calculate the pH when a. 16.0 mL of NaOH is added b. 24.0 mL of NaOH is added 30.0 mL of NaOH is added c. HCIO4(aq) + NaOH(aq) NaCIO4(aq) + H2O(1)

Which of the following, when mixed, would NOT result in a buffer solution? а. 10 mL of 0.1M HCI and 20 mL of 0.1 M NH3 O b. 10 mL of 0.1 M HCI and 20 mL of 0.1 M NaC2H3O2 C. 10 mL of 0.1 M NaOH and 20 mL of 0.1 M potassium cyanide, KCN d. 10 mL of 0.1 M NaOH and 20 mL 0.1 M HF e. 10 mL of 0.1 M acetic acid, HC2H3O2, and 10 mL of 0.1 M sodium acetate, NaC2H3O2

Hh.129.

5. A 1.0M solution of HCI is titrated with a 1.M solution of NaOH to an equivalence point of pH 7. If the 1.0M solution of HCI was titrated with a more dilute solution of NaOH would the equivalence point change? 6. Is the titration process limited to reactions between acids and bases?

A sample weighing 1.25 g of the diprotic acid potassium acid phthalate (KHP) is dissolved in 50.0 ml of water. Consider the titration of this solution with 0.100 M NaOH. The two Ka’s for KHP are 1.12 x 10-3 and 3.90 x 10-6.   a. Calculate the pH of this solution before adding any NaOH.   b. How many ml of NaOH must be added to reach the equivalence point? What is the pH at the equivalence point?     c. Calculate the pH of the solution after 100. ml of NaOH have been added.

22. Which of the following mixture could be considered as a buffer? Hint: Try to react each mixture (if possible) and look for a pair that could be components for the buffer c. HC1 + CF d. CH3COO+ OH- a. NH4C1 + NAOH b. NH3 + NaOH 23. What is the pH of a buffer solution containing 0.25 M acetic acid and 0.030 M sodium acetate? The acid dissociation constant for acetic acid is equal to 1.8 x 10 Hint no dilution occurred a. 3.82 b. 5.67 C. 10.18 d. 8.34

6. Consider a solution that has 0.00500 M HCl and 0.100 M HF. Ka of HF = 7.2x10-4. a. What is the pH of this solution? b. Suppose the solution was like that in A but also had 0.1 M HOI. (i.e. total solution was a mix of 0.00500 M HCl, 0.100 M HF, and 0.1 M HOI). Ka of HOI = 2.0x10-¹¹. Does this solution have an appreciably different pH than the solution in part a? Support your answer with relevant calculations. HINT: Work from strongest acid to the weakest acid.

7. A solution was made by mixing 50.0 mL of 0.750 M HCN with 25.0 mL of water. What is the pH of this solution? The pka of HCN = 9.31. 8. One of the compounds featured on the TV series "Breaking Bad" was hydrofluoric acid (HF), pKa = 3.14. a) A solution of HF has a pH = 1.77. What was the initial [HF] for this solution in mol L-1? b) What is the equilibrium concentration of F in this solution in mol L-1? c) What is the percent ionization of HF in this solution?