Difference Between Condensation and Hydrolysis

Main Difference – Condensation vs Hydrolysis

Chemical reactions take place everywhere in the environment. Condensation and hydrolysis are two types of chemical reactions that involve synthesis or cleavage of chemical bonds. Condensation reactions occur through the formation of a larger molecule from smaller reactant molecules. Hydrolysis reactions occur through the formation of smaller molecules from a larger reactant molecule. Therefore, condensation involves the formation of a new chemical bond while hydrolysis involves the breakdown of a chemical bond. The main difference between condensation and hydrolysis is that condensation produces a smaller molecule as a byproduct whereas hydrolysis does not produce a byproduct.  

Key Areas Covered

1. What is Condensation
      – Definition, Mechanism, Examples
2. What is Hydrolysis
      – Definition, Mechanism, Examples
3. What is the Difference Between Condensation and Hydrolysis
     – Comparison of Key Differences

Key Terms: Condensation, Dehydration Synthesis, Hydrolysis, Saponification

What is Condensation

Condensation is a chemical reaction that involves the synthesis of a complex molecule from small reactant molecules. This is called a condensation reaction because a small molecule is released as a byproduct of the reaction. This small molecule can be a water molecule, HCl molecule, methanol, etc.

When the released by product is a water molecule, it is called a dehydration synthesis reaction. This is because a complex molecule is formed from small reactant molecules releasing a water molecule as a byproduct. Therefore, in dehydration synthesis reactions, -OH group of one reactant and the –H group of another reactant are released. But if a –Cl group is released instead of –OH group, then the byproduct of the reaction would be an HCl molecule.

Figure 01: Amino Acid Condensation

Condensation reactions are used in the production of polymers. Polymerization process which produces polymer molecules using condensation reactions are called condensation polymerization. Here, a number of monomer units are attached to each other, resulting in a small molecule as a byproduct per each bond. This byproduct is often a water molecule or an HCl molecule.

What is Hydrolysis

Hydrolysis is the breakdown of a large reactant molecule into small products in the presence of water. Water is an essential reactant molecule in hydrolysis reactions. The reactant of hydrolysis is a complex molecule whereas products of hydrolysis are small molecules or fragments. Therefore, it is the opposite of the dehydration synthesis reaction.

Water molecule provides a hydroxyl group (-OH) and a proton (-H group) for the products. Therefore, for each chemical bond that is being cleaved, one water molecule is consumed. This indicates that hydrolysis reactions proceed with the consumption of water molecules.  

Figure 02: Hydrolysis of a Disaccharide into Monosaccharides

One common example for hydrolysis is saponification. Here, an ester is cleaved into a carboxylate ion and an alcohol. This reaction takes place when a base is added to an aqueous solution of ester. Then the water molecules provide e-H groups and –OH groups required for the hydrolysis of ester.

Difference Between Condensation and Hydrolysis

Definition

Condensation: Condensation is a chemical reaction that involves the synthesis of a complex molecule from small reactant molecules.

Hydrolysis: Hydrolysis is the breakdown of a large reactant molecule into small fragments in the presence of water.

Reactants

Condensation: The reactants of condensation reactions are small molecules when compared to their products.

Hydrolysis: The reactants of hydrolysis reactions are complex molecules when compared to their products.

Products

Condensation: The products of a condensation reaction are complex molecules along with a small molecule such as H₂O, HCl, CH₃OH, etc.

Hydrolysis: The products of hydrolysis includes small fragments or molecules from which the complex molecule is made of.

Byproducts

Condensation: Condensation reactions produce water as a byproduct.

Hydrolysis: Hydrolysis does not produce water as a byproduct.

Water Molecule

Condensation: Condensation reactions synthesize water.

Hydrolysis: Hydrolysis reactions consume water.

Conclusion

Condensation and hydrolysis are chemical reactions. Condensation is a combination reaction whereas hydrolysis is a decomposition reaction. Hydrolysis always includes water as a reactant. Condensation sometimes give water as a product. The main difference between condensation and hydrolysis is that condensation produces a smaller molecule as a byproduct whereas hydrolysis does not produce a byproduct. 

References:

1. Boundless. “Condensation Reactions – Boundless Open Textbook.” Boundless. Boundless, 08 Aug. 2016. Web. Available here. 09 Aug. 2017.
2. “Hydrolysis.” Chemistry Explained. N.p., n.d. Web. Available here. 09 Aug. 2017.

Image Courtesy:

1. “AminoacidCondensation” Von V8rik at en.wikipedia – Eigenes Werk (Gemeinfrei) via Commons Wikimedia
2. “Figure 03 01 02” By CNX OpenStax – (CC BY 4.0) via Commons Wikimedia