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Buffer Solution

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Submitted By sanjugautam
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BUFFER SOLUTION
Buffer solution is a solution which resist any change in its pH an addition of strong acid or alkali.
Types
1 Mixture of weak acids with their salt with strong base i.e. (weak acid + salt of weak acid , conjugated base)
2 Mixture of weak bases with their salt with strong acid i.e. (weak base + salt of weak acid , conjugated acid)
Examples:
H2CO3/NaHCO3(Bicarbonate buffer)
(Carbonic acid and Sodium Carbonate)
CH3COOH/CH3COONa(Acetate buffer)
(Acitic acid and Sodium acetate)
Na2HPO4/NaH2PO4(phosphate buffer)
Buffer capacity:
Buffering capacity is the no. of grams of strong acids or alkali which is necessary for a change in pH of one unit of one lit. of buffer solution.
Axn:
When HCl or NaOH is added to acetate buffer * CH3COONa + HCl→CH3COOH + NaCl * CH3COOH + NaOH→CH3COONa + H2O
Thus change in pH is minimized
BUFFER OF THE BODY FLUIDS
Cellular metabolism predominantly yields acids so it is approcipriate that body buffer has buffering capacity to absorb acids are first line of defense against acid load.

a Bicarbonate buffer system ( H2CO3/NaHCO3)
% of buffering capacity,
Plasma- 65%
Whole body- 40%
CO2 and H2CO3 can freely diffuse across the cell membrane and vascular capillary epithelium.
Regulation,
Base constituents-kidney (metabolic component)
Acid constituents –respiration (Respiratory)
Salt / Acid – 20

b. Phosphate buffer system (Na2HPO4/NaH2PO4)
Primary intracellular buffer, its concentration in plasma is vary low
Salt /Acid-4 c. Protein buffer systems
Buffering capacity of proteins depends on the pKa value of ionizable side chains.
The most effective group is histidine imidazol group with pKa value 6.1 * Albumin -16 histidine * Hemoglobin -38 histidine

BUFFER SYSTEM OF THE BODy Extracellular fluid | Intracellular fluid | Erythrocyte fluids |...

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