Difference Between Dissociation and Solvation

The key difference between dissociation and solvation is that dissociation is the breakdown of a substance into the atoms or ions from which the substance is made of whereas solvation is the dissolution of a substance in a solvent due to the attraction forces between the solvent molecules and the components of the substance.

Dissociation and solvation are often found in analytical chemistry and in inorganic chemistry, regarding the breakdown of chemical substances upon different interactions between atoms and ions in a substance.

CONTENTS

1. Overview and Key Difference
2. What is Dissociation
3. What is Solvation
4. Side by Side Comparison – Dissociation vs Solvation in Tabular Form
5. Summary

What is Dissociation?

The term dissociation refers to the breakdown or split of a compound into smaller particles. The dissociation process forms products that are either electrically charged or neutral. That means; the products of dissociation can be either ionic or non-ionic. However, this does not involve the gain or loss of electrons by the atoms.

In contrast to the process of ionization, dissociation involves the separation of ions that already existed in a compound. Sometimes, dissociation may also produce neutral particles—for example, the breakdown of N₂O₄ results in the production of two molecules of NO₂. Dissociation processes are reversible most of the times. That means, separated ions can be re-arranged to produce the previous compound. For example, as mentioned above, the dissolving of NaCl is a dissociation process, and it produces two charged particles. But, solid NaCl can be obtained again with given proper conditions, which proves that dissociation is reversible. Unlike ionization, dissociation takes place in ionic compounds.

What is Solvation?

Solvation is the dissolution of a substance in a particular solvent. The solvation occurs due to the attraction force between molecules of the solvent and the solute molecules. Usually, the attraction forces involved in this process are ion-dipole bonds and hydrogen bonding attractions. These attraction forces cause the dissolution of a solute in a solvent.

The ion-dipole interactions can be found between ionic compounds and polar solvents. E.g. water is a polar solvent. When sodium chloride is added to water, the polar water molecules attract the sodium ions and chloride ions separately, which causes the sodium and chloride ions to break apart. This results in the breakdown of the sodium chloride ionic compound.

What is the Difference Between Dissociation and Solvation?

Dissociation and solvation are terms that describe how different substances break into small pieces or atoms/ion depending on the interactions. The key difference between dissociation and solvation is that dissociation is the breakdown of a substance into the atoms or ions from which the substance is made of whereas solvation is the dissolution of a substance in a solvent due to the attraction forces between solvent molecules and the components of the substance.

Below tabulation shows more differences between dissociation and solvation.

Summary – Dissociation vs Solvation

The key difference between dissociation and solvation is that dissociation is the breakdown of a substance into the atoms or ions from which the substance is made of whereas solvation is the dissolution of a substance in a solvent due to the attraction forces between solvent molecules and the components of the substance.

Reference:

1. “Solutions, Solvation, and Dissociation.” Chemistry LibreTexts, Libretexts, 5 June 2019, Available here.
2. “Solvation and Dissociation.” Socratic.org, Available here.

Image Courtesy:

1. “BrOH acid dissociation” By Achow801 – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “214 Dissociation of Sodium Chloride in Water-01” By OpenStax College – Anatomy & Physiology, Connexions Web site, Jun 19, 2013 (CC BY 3.0) via Commons Wikimedia