Question 2 2/2 pts If the pka of HCHO2 is 3.74 and the pH of an...

Question 2 2/2 pts If the pka of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.89, which of the following is TRUE? It is not possible to make a buffer of this pH from HCHO2 and NaCHO2. [HCHO2] = [NaCHO2] [HCHO2] >>[NaCHO2] [HCHO2] < [NaCHO2] [HCHO2] > [NaCHO2]

Question 3 1.33/2 pts Acid #1 has a pka of 3.15 Acid #2 has a pka of 3.65 Acid #3 has a pka of 4.23 Acid #4 has a pKa of 4.79 You are asked to make a buffer of pH 3.4 and given the above acids. Of these acids, which would create a buffer with the best capacity against acids? Which would have the best buffering capacity against bases? Which could not be used at all for this project? Best against acids Acid #2 Best against bases Acid #1 Cannot be used Acid #4

Question 4 2/6 pts You have two acid substances, A and B. You believe A is a weak acid and B is a strong acid. To find out if you're right you do three experiments. You prepare equal molarity solutions of A, B and NaOH. Exp #1, you mix equal volumes of your A solution with your NaOH solution and check it's pH. Exp #2, you mix equal volumes of your B solution with your NaOH solution and check it's pH. Exp #3, you mix a volume of your NaOH solution with twice the volume of your A solution and check it's pH. If your beliefs were correct, what would you find the pH in each experiment? Exp #1 pH <7 Exp #2 pH = 7 Exp #3 pH > 14