How does the surface tension of a liquid vary with increase in temperature ?

Options

A. Remains same
B. Decreases
C. Increases
D. No regular pattern is followed

Answer

B

Explanation

Surface tension of liquids decrease with increase of temperature and at critical temperature. It become zero. The decrease in surface tension with increase of temperature is due to the fact that with increase of temperature, kinetic energy of the moleules increases and hence, the intermolecular attraction decreases.
Note : Surface tension of a liquid is said to be the force acting at right angles to the surface along 1 cm length of the surface. Units of surface tension are dyne per cm (or newtons per metre i.e., `Nm^(-1)` in the SI systems).