How does the addition of salt to water affect its surface tension?

How does the addition of salt to water affect its surface tension?

Step 1: Understand what surface tension is. Surface tension is the property of a liquid that makes its surface behave like a stretched elastic sheet.
Step 2: Know that water molecules are attracted to each other. This attraction is called cohesion, and it helps create surface tension.
Step 3: Learn that when salt (sodium chloride) is added to water, it breaks into positive and negative ions.
Step 4: Recognize that these ions interact with water molecules. The positive ions attract the negative parts of water molecules, and the negative ions attract the positive parts.
Step 5: Understand that these interactions increase the attraction between water molecules, enhancing cohesion.
Step 6: Conclude that because the cohesive forces among water molecules are stronger with salt, the surface tension of the water increases.

Surface Tension – The property of the surface of a liquid that allows it to resist an external force, due to cohesive forces between liquid molecules.
Ionic Interactions – The interactions between charged ions that can influence the physical properties of a solution, such as surface tension.
Cohesive Forces – The attractive forces between molecules of the same substance, which play a key role in determining surface tension.