Question

Why surface tension curve for ethanol is decreasing?

Answer 1

Answer:

Water has a high surface tension because it is strongly attracted to itself. However, if you add alcohol, instead of water interacting only with other water molecules, it now interacts (less strongly) with alcohol, and the surface tension of the mixture will be lower.

Answer 2

$\huge \fbox \red{Answer}$

Water has a high surface tension because it is strongly attracted to itself. However, if you add alcohol, instead of water interacting only with other water molecules, it now interacts (less strongly) with alcohol, and the surface tension of the mixture will be lower.