Given :
pH of solution of mixture of lactic acid and lactate is 4.26 .
To Find :
The ratio of the lactate concentration to the lactate .
Solution :
We know , pKa of lactic acid is :
pKa = 3.86 .
Now , the solution of lactic acid and lactate is a buffer solution .
So , pHof buffer acid is given by :
Putting all given values :
Taking anti log both the sides , we get :
Therefore , the ratio of the lactate concentration to the lactate is 2.51 .
Hence , this is the required solution .
Answer:
a) [Tris0] : [Tris] = 1 : 100
b) Range = 7.1 to 9.1
Explanation:
a) Calculation of ratio of the basic and the acidic forms of tris
pH of a buffer is calculate using Henderson-Hasselbalch equation
Conjugate acid of Tris dissociated as
For tris,
Salt or Basic form = tris0
Acid or Acidic form = Tris
pKa = 8.1
pH = 6.1
[Tris0] : [Tris] = 1 : 100
b) Range of Tris
Range of any buffer is:
From (pKa -1) to (pKa+1)
So, range of Tris is:
From (8.1 - 1) to (8.1 +1)
or from 7.1 to 9.1