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Submitted to:
Shah Marzia Mahjabin Lina
Assistant Professor
Department of Pharmacy
Stamford University Bangladesh
Submitted by:
Name: Sujon Mia
ID: BPH-06707425
Batch No: 067
Stamford University Bangladsh
Mid Assessment 2 : Presentation on
Buffer solution
Course: Pharmaceutical analysis
Course Code: BPH 325
Batch:67
What is buffer solution?
Buffer Solution resist a change in pH upon dilution or
upon the addition of small amounts of acid or base.
There are two types of buffer solution
1. Acidic Buffer
2. Basic Buffer
Acidic Buffer: A weak acid together with a salt of the same acid with
a strong base. There are called Acidic Buffer.
or Example. CH3COOH + CH3COONa
Basic Buffers: A weak base and its salt with a strong acid. There
are called Basic Buffers.
Example: NH4OH +NH4Cl
Properties of Buffer Solution
Buffer solutions are certainly resistant to changes in pH. However, the pH of a
buffer solution can change if there is an addition of sufficient strong acid or strong
base.
Buffer capacity refers to the amount of strong acid or base a buffer solution can
take before significant pH changes take place. It is a measure of the resistance of a
buffer solution to pH change on the addition of hydroxide ions.
Mechanism of Buffer Action
In solution, the salt is completely ionized and the weak acid is partly
ionized. CH3COONa ⇌ Na+ + CH3COO–
CH3COOH ⇌ H+ + CH3COO–
On Addition of Acid and Base
1. On addition of acid, the released protons of acid will be
removed by the acetate ions to form an acetic acid
molecule. H+ + CH3COO– (from added acid) ⇌
CH3COOH (from buffer solution)
2. On addition of the base, the hydroxide released by the base
will be removed by the hydrogen ions to form water. HO–
+ H+ (from added base) ⇌ H2O (from buffer solution)
Preparation of Buffer Solution
 If the dissociation constant of the acid (pKa) and of the
base (pKb) are known, a buffer solution can be prepared
by controlling the salt-acid or the salt-base ratio.
 As discussed earlier, these solutions are prepared by
mixing the weak bases with their corresponding
conjugate acids, or by mixing weak acids with their
corresponding conjugate bases.
Application of Buffer Solution
Buffer solutions certainly have a massive range of applications.
The applications of buffer solutions are for both the real world and
the lab.
 A buffered pH is a necessity of most enzymes to function
efficiently and correctly.
Furthermore, buffering is important for ensuring proper colour
concentration when using dyes.
Buffer solutions whose preparation takes place from acetic acid,
citric acid, ammonia, can have pH values as high as 10 or as low as
2.
This allows buffer solutions to be worked with very strong bases
or acids.
There exists a few alternate names that are used to refer
buffer solutions, such as pH buffers or hydrogen ion
buffers.
An example of the use of buffers in pH regulation is the
use of bicarbonate and carbonic acid buffer system in
order to regulate the pH of animal blood.
 Buffer solutions are also used to maintain an optimum
pH for enzyme activity in many organisms.
Uses of Buffer Solutions
Thank you