Which of the following liquids has the highest surface tension?

The correct answer is Water.
Key Points

• Surface tension is the measure of the force required to stretch or break the surface of a liquid.
  • The SI unit of Surface Tension is Newton per Meter or N/m.
  • It is important to note that the surface tension of a liquid is dependent on factors such as temperature, pressure, and impurities.
• Water (H₂O) has the highest surface tension among the given options due to its strong hydrogen bonding between the water molecules.
  • This results in a strong cohesive force between the molecules, making it difficult to break the surface.

Additional Information

• Ethanol (CH₃CH₂OH) is a volatile, colorless liquid that has a slight odor.
  • It burns with a blue flame that is smokeless and sometimes invisible in normal light.
• Ethane (C₂H₆) is a gas at room temperature and does not have a surface tension value.
  • At standard temperature and pressure, ethane is a colorless, odorless gas. ​
• Methanol (CH₃OH), also known as wood alcohol, is considered an alternative fuel.
  • It is often used as a low surface tension testing substance in calibration and/or testing of new apparatuses or methods to measure surface tension.

Important Points

Boiling points of some compounds at atmospheric pressure 1 atm :