The key difference between isosmotic hyperosmotic and hypoosmotic is that isosmotic refers to the property of having equal osmotic pressures. But, hyperosmotic refers to the property of having a high osmotic pressure and hypoosmotic refers to the property of having a low osmotic pressure.
Osmotic pressure is the pressure that would have to be applied to a pure solvent to prevent it from passing into a given solution by osmosis. Often, we use this term to express the concentration of the solution. Moreover, the term osmotic pressure also describes the pressure that is responsible for the passing of solutes from one side to the other side through a semipermeable membrane.
CONTENTS
1. Overview and Key Difference
2. What is Isosmotic
3. What is Hyperosmotic
4. What is Hypoosmotic
5. Side by Side Comparison – Isosmotic Hyperosmotic vs Hypoosmotic in Tabular Form
6. Summary
What is Isosmotic
The term isosmotic refers to the property of having equal osmotic pressures. This means the number of solute molecules in one side of the semipermeable membrane is equal to the number of solute molecules on the other side. Therefore, there is no net movement of solute molecules through the semipermeable membrane via osmosis since the solute molecules move from high concentration to a low concentration through a concentration gradient.
Figure 01: Concept of Osmotic Pressure
What is Hyperosmotic?
The term hyperosmotic refers to the property of having a high osmotic pressure. That means; the number of solute molecules in one side of the semipermeable membrane (in the sample solution) is higher than the number of solute molecules on the other side. Therefore, there we can observe a net movement of solute molecules through the semipermeable membrane via osmosis.
What is Hypoosmotic?
The term hypoosmotic refers to the property of having a low osmotic pressure. That means; the number of solute molecules in one side of the semipermeable membrane (in the sample solution) is lower than the number of solute molecules on the other side.
Figure 02: Tonicity has the Same Idea as Osmolarity
In hypoosmotic solutions, we can observe a net movement of solute molecules through the semipermeable membrane via an osmosis concentration gradient.
What is the Difference Between Isosmotic Hyperosmotic and Hypoosmotic?
Osmotic pressure is the pressure that would have to be applied to a pure solvent to prevent it from passing into a given solution by osmosis. The key difference between isosmotic hyperosmotic and hypoosmotic is that the term isosmotic refers to the property of having equal osmotic pressures and the term hyperosmotic refers to the property of having high osmotic pressure, and meanwhile, the term hypoosmotic refers to the property of having a low osmotic pressure.
Therefore, in isosmotic solutions, there is no net movement since osmotic pressure is equal. But, in hyperosmotic solutions, solutes move from the solution to surrounding since osmotic pressure of the solution is higher than that the solution. In contrast, in hypoosmotic solutions, solutes move into the solution from the surrounding since the osmotic pressure of the solution is lower than the surrounding.
Below infographic compares the difference between isosmotic hyperosmotic and hypoosmotic in tabular form.
Summary – Isosmotic vs Hyperosmotic vs Hypoosmotic
Osmotic pressure is the pressure that would have to be applied to a pure solvent to prevent it from passing into a given solution by osmosis. The key difference between isosmotic hyperosmotic and hypoosmotic is that isosmotic refers to the property of having equal osmotic pressures, but hyperosmotic refers to the property of having a high osmotic pressure. Meanwhile, hypoosmotic refers to the property of having a low osmotic pressure.
Reference:
1. Helmenstine, Anne Marie. “Osmotic Pressure and Tonicity.” ThoughtCo, Feb. 11, 2020, Available here.
2. “Osmotic Pressure.” Chemistry LibreTexts, Libretexts, 5 June 2019, Available here.
3. “What Is Osmotic Pressure? What Is Isosmotic? What Is Hyposmotic?” OneClass, 14 May 2019, Available here.
Image Courtesy:
1. “Osmotic pressure” By Nkonopli – Own work, (Public Domain) via Commons Wikimedia
2. “Osmotic pressure on blood cells diagram” By LadyofHats (Public Domain) via Commons Wikimedia