Posted by ALISON on .
1.CALCULATE pH of 1.0 L 0.010 M ascetic acid and 0.50 L 0.010 M NaOH.
2. Calculate pH of 1.0 L 0.010 M NaOH and 0.500 L 0.010M HCl
Call acetic acid, HAc.
.........HAc + NaOH ==> NaAc + H2O
mols HAc initially = 0.01M x 1L = 0.01.
mols NaOH added = 0.01 x 0.5L = 0.005.
Soyou have used up 1/2 the HAc and formed NaAc and you have no NaOH left unreacted.
The soln consists of 0.005 mols NaAc and 0.005 mol HAc.
Use the Henderson-Hasselbalch equation to calculate pH.
2. This is done the same way EXCEPT that it is not a buffer and you don't use the HH equation. You are left with NaCl as the salt and an excess of either acid or base from which the pH can be determined.