The key difference between carbonic acid and bicarbonate is that carbonic acid is a neutral chemical compound, whereas bicarbonate is a negatively charged chemical compound.
Carbonic acid is a weak acid that forms in solution when carbon dioxide dissolves in water, with the chemical formula H2CO3. Bicarbonate forms by the combination of three oxygen atoms, a hydrogen atom, and a carbon atom with the chemical formula HCO3-.
CONTENTS
1. Overview and Key Difference
2. What is Carbonic Acid
3. What is Bicarbonate
4. Carbonic Acid vs Bicarbonate in Tabular Form
5. Summary – Carbonic Acid vs Bicarbonate
What is Carbonic Acid?
Carbonic acid is H2CO3. Sometimes, we give this name to solutions having carbon dioxide dissolved in water or carbonated water. This is because carbonated water contains a small amount of H2CO3. Furthermore, carbonic acid is a weak acid, and it can form two types of salts as carbonates and bicarbonates. The molar mass of this compound is 62.024 g/mol.
Figure 01: The Chemical Structure of Carbonic Acid
When carbon dioxide dissolves in water, it enters an equilibrium between carbon dioxide and carbonic acid. The equilibrium is as follows:
CO2 + H2O ⟷ H2CO3
If we add an excess of carbonic acid to a base, it gives bicarbonate. But, if there is an excess of base, then carbonic acid tends to give carbonated salts. More precisely, carbonic acid is a carboxylic acid compound that has two hydroxyl group substituents attached to the carbonyl carbon. Moreover, it is a polyprotic acid, which is capable of donating protons. It has two removable protons, so it is specifically diprotic.
What is Bicarbonate?
Bicarbonate forms by the combination of three oxygen atoms, a hydrogen atom, and a carbon atom. The product of this combination can be an ion or a compound with more electrons than protons. We can describe it as a chemical species having the chemical formula HCO3–.
Figure 02: The Chemical Structure of Bicarbonate Anion
This compound is a crucial part of the body’s pH buffering system, in layman terms: it is responsible for keeping one’s blood in a state that is not too acidic or too basic. In addition, it serves as a way of keeping the digestive juices in check once the stomach has finished digesting the food. Furthermore, carbonic acid in rainwater forms bicarbonate ions when it hits rocks. This flow of bicarbonate ions is important in keeping the carbon cycle going.
What is the Difference Between Carbonic Acid and Bicarbonate?
Carbonic acid is a weak acid that forms in solution when carbon dioxide dissolves in water, and its chemical formula is H2CO3. Bicarbonate forms by the combination of three oxygen atoms, a hydrogen atom, and a carbon atom with the chemical formula HCO3-. The key difference between carbonic acid and bicarbonate is that carbonic acid is a neutral chemical compound, whereas bicarbonate is a negatively charged chemical compound. Moreover, carbonic acid is used in making bubbly, fizzy drinks, treating dermatitides, in mouthwash, etc., while bicarbonate is used in food preparations such as baking (as a leavening agent), and it gives the ability to resist changes in pH.
The following infographic summarizes the difference between carbonic acid and bicarbonate in tabular form for side by side comparison.
Summary – Carbonic Acid vs Bicarbonate
Carbonic acid is H2CO3. Bicarbonate forms by the combination of three oxygen atoms, a hydrogen atom and a carbon atom, with the chemical formula HCO3-. The key difference between carbonic acid and bicarbonate is that carbonic acid is a neutral chemical compound, whereas bicarbonate is a negatively charged chemical compound.
Reference:
1. “What Are Bicarbonates? – Structure, Uses & Health Effects of Bicarbonates.” BYJU’S, 19 Aug. 2021.
Image Courtesy:
1. “Carbonic acid 2D” By Eetwartti – Own work based on Image:Carbonic-acid-2D.png (Public Domain) via Commons Wikimedia
2. “Bicarbonate resonance” By Hellbus – Own work (CC BY-SA 3.0) via Commons Wikimedia