Bicarbonate can react with hydrogen ions to form carbonic acid, which combines with water to produce carbon dioxide and more water. The carbon dioxide is expired through the lungs thus helping maintain pH equilibrium in the body.
H20 + CO2<------->H2C03<------->H+ + HC0-3
Water + Carbon Dioxide combine under the influence of the enzyme Carbonic Anhydrase to form Carbonic Acid, which then spontaneously disassociates to form Hydrogen + Bicarbonate Ion.
as well as the reverse:
Hydrogen + Bicarbonate ions combine to form Carbonic Acide which under influence of Carbonic Anhydrase then forms water + Carbon Dioxide.
Bicarbonate itself (HCO3-) is NOT a buffer but a single compound.
A buffer is always a mixture of a weak acid and its conjugated (mono-protonated) weak base.
Possible reactions of bicarbonate (HCO3-) in water:
Reading this carefully will bring into mind the two possible buffering mixtures:
The bicarbonate ion accepts more Hydrogen ions to make the strong acid a weaker acid.
A buffer solution contains a strong acis and its conjugate base of a strong base and its conjugate acid.
Carbonates and bicarbonates are main part of blood buffer system , derived from carbonic acid hence called carbonic acid buffer system .
The blood contains buffers like bicarbonate and phosphate buffers. The bicarbonate buffer is by far, the most important.
The most important buffer for maintaining acid-base balance in the blood is the carbonic acid-bicarbonate buffer.
bicarbonate (base)
An important physiological buffer is the Digestive System's Bicarbonate Buffer System: CO2 + H2O = H2CO3 = H+ + HCO3- The bicarbonate ion (HCO3-) is made by the pancreas. This is one of the pancrea's many exocrine functions. The bicarbonate helps to counteract the HCl released into the stomach thus maintaining the pH balanced.
There are many buffers in the body. These buffers can be found in the mouth and in the stomach to aid in digestion.
The buffer system that operates in blood plasma is the bicarbonate buffering system. The chemical equation for this system is the following CO2 + H2O <--> H2CO3 <--> HCO3- + H+.
bicarbonate buffer is instant, followed by respiratory, renal, and phosphate.
Bicarbonate Buffer System (only important ECF buffer)
1. Bicarbonate buffer system 2. Protein buffer system 3. Phosphate buffer system
The blood contains buffers like bicarbonate and phosphate buffers. The bicarbonate buffer is by far, the most important.
Buffer systems help to maintain constant plasma pH. There are three buffer systems: Protein buffer system, phosphate buffer system and bicarbonate buffer system. Among these, the bicarbonate buffer system is the most predominant. Buffer Systems function as "shock absorbers" that accept excess H+ ions or OH- ions and keep blood pH constant. For example, if there is an increase in acidity of blood due to excess HCl (a strong acid), then NaHCO3 (Sodium bicarbonate) will buffer it to a weak acid (H2CO3). HCl+NaHCO3 = NaCl+H2CO3
The most important buffer for maintaining acid-base balance in the blood is the carbonic acid-bicarbonate buffer.
bicarbonate (base)
the bicarbonate ion
Buffer systems help to maintain constant plasma pH. There are three buffer systems - Protein buffer system, phoshate buffer system and bicarbonate buffer system. Among this, bicarbonate buffer system is the most predominant. Buffers function as "shock absorbers" that accept excess H+ ions or OH- ions and keep blood pH constant. For example, if there is an increase in acidity of blood due to excess HCl (a strong acid), then NaHCO3 (Sodium bicarbonate) will buffer it to a weak acid (H2CO3). HCl+NaHCO3 = NaCl+H2CO3
The Bicarbonate Buffer System
bicarbonate buffer system