Factors affecting surface tension

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SUMMARY

Surface tension is affected by temperature and the presence of impurities. Specifically, temperature is inversely related to surface tension; as temperature increases, surface tension decreases. The addition of soluble impurities, such as methanol and ethanol, can also decrease surface tension, while sparingly soluble impurities like n-pentanol can decrease it more effectively due to their molecular structure. The molecules at the surface experience a net downward force, behaving like a stretched membrane.

PREREQUISITES
  • Understanding of surface tension principles
  • Knowledge of molecular interactions and solubility
  • Familiarity with the effects of temperature on physical properties
  • Basic chemistry concepts related to polar and nonpolar molecules
NEXT STEPS
  • Research the relationship between temperature and surface tension in liquids
  • Explore the effects of different soluble and sparingly soluble impurities on surface tension
  • Investigate the molecular structure of alcohols and their impact on surface properties
  • Learn about the physical behavior of liquids at the molecular level, particularly in relation to surface tension
USEFUL FOR

Chemists, materials scientists, and anyone studying the physical properties of liquids and their interactions with various impurities.

Kaushik
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I read the following two points:
  • Temperature is indirectly proportional to surface tension.
  • Adding impurities affect the surface tension of the molecules. Adding soluble impurities increases the surface tension whereas adding sparingly soluble impurity decreases the surface tension.
Why?

Edit: Also, could you please clarify the following: The molecules on the surface experiences a net downward force and hence acts like a stretched membrane. Why does it act like a stretched membrane?
 
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Usually the surface tension decreases when temperature is increased.

Soluble impurities can also decrease surface tension, for example methanol or ethanol added to water. Larger-molecule alcohols like n-pentanol that aren't completely water soluble will decrease the surf. tension more effectively because they have a polar and nonpolar end like soap molecules. I don't think there is any general rule relating the solubility of an impurity and its effect on this physical property.
 
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hilbert2 said:
Usually the surface tension decreases when temperature is increased.

Soluble impurities can also decrease surface tension, for example methanol or ethanol added to water. Larger-molecule alcohols like n-pentanol that aren't completely water soluble will decrease the surf. tension more effectively because they have a polar and nonpolar end like soap molecules. I don't think there is any general rule relating the solubility of an impurity and its effect on this physical property.
Why does it decrease with temperature? Please check the edit.
 

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