BUFFERS
INSTRUCTIONS:
Answer the problems below. Show complete solutions (15 pts each)
Make a flowchart of procedures to take to prepare the said buffers for each iteration (10 pts each)
Make use of the following information for your solutions:
The following table gives the acid-dissociation constant values for carbonic acid H2CO3 and phosphoric acid, H3PO4:
Acid
Ka1
Ka2
Ka3
H2CO3
4.3 * 10^-7
5.6 * 10^-11
N/A
H3PO4
7.2 * 10^-3
6.2 * 10^-8
4.2 * 10^-13
PROBLEMS:
1. What is the pH of the buffer solution formed by combining 50 g of NaH2PO4 and 80 g of NaHPO4 in 300 ml of water?
2. Compute the pH of an acetate buffer produced by mixing 500 ml of a 0.5 M NaHCO3 solution and 300 ml of a 0.25 M HCO3- solution.