Question

Which of the following has the least surface tension?

• A. Methanol
• B. Acetic acid
• C. Diethyl ether
• D. Chlorobenzene

Answer 1

The correct option is C

Diethyl ether

Explanation for Correct Option (C):

Surface Tension:

• This is the tension caused by the liquid film, which is caused by the bulk of the liquid's attraction to the particles in the surface layer and tends to reduce the surface area.
• We already know that the shape of a liquid drop is determined by surface tension.
• Now consider what happens when there is a force of attraction between the particles.
• If, on the other hand, the presence of vapour pressure determines the adhesive force, we must know that the higher the vapour pressure, the lower the surface tension.
• Vapour pressure, on the other hand, is the pressure exerted by vapour. Diethyl ether has the highest vapour pressure and the lowest surface tension of the three.

Explanation for Incorrect Options:

• Because methanol and acetic acid have hydrogen bonding (a strong attraction), they have a low vapour pressure and a high surface tension.
• Because of its polarity, chlorobenzene has a higher surface tension than di-ethyl ether.

Therefore, option C is the correct answer.