47.25 mL of 0.1120 M Acetic acid titrated with 0.4750 M KOH. Calculate the initial pH, and the pH at the equivalence point of titration? Acetic Acid Dissociation Constant: 1.75 x 10 -5
1 Answer
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The initial pH is
So, you start with a solution of acetic acid. The pH of this solution can be determined by using the concentration of protons in solution. For that, you'll have to set up an ICE chart
....
I.....0.1120..................................0.........................0
C....(-x).....................................(+x)......................(+x)
E...(0.1120-x)............................x...........................x
Use the expression of the acid dissociation constant to solve for
The value you'll get for
Now you begin the titration by adding
Notice that you have a
The number of moles of acetic acid you have in solution is
Automatically, both the acetic acid and the potassium hydroxide will be consumed in the reaction; the
Now, you'll need to determine the total volume of the solution; for this you must determine how much
The total volume of the solution will be
Use this volume to determine the concentration of the potassium acetate formed in solution
After the acetic acid and ptoassium hydroxide are consumed,
.....
I......0.09704..................................................0.......................0
C.....(-x)..........................................................(+x)...................(+x)
E...(0.09704 - x)............................................x.........................x
This time use the base dissociation constant, or
Use this to determine
Plug this baby into this equation to solve for the final pH