PART A:
Suppose you wanted to make a buffer of exactly pH 7.00 using KH 2 PO 4 and Na 2 HPO 4 . If the final solution was 0.10 M in KH 2 PO 4 , what concentration of Na 2 HPO 4 would you need? ( p K a for H 3 PO 4 , H 2 PO − 4 , and HPO 2− 4 are 2.14, 6.86, and 12.40, respectively.) ANS: 0.14 M
PART B:
Now assume you wish to make a buffer at the same pH (7), using the same substances, but want the total phosphate molarity ([HPO2−4]+[H2PO−4]) to equal 0.30. What concentration of the KH2PO4 would be required? (PLEASE HELP ME SOLVE PART B)
