Surface Tension Test - 10

The shape of a liquid drop is tend to minimize the surface tension by minimizing its surface area.

The angle of contact with wall of container is angle b/w liquid surface & normal to the wall of container. Hence for a plane liquid angle of contact is 0⁰.

It require minimum surface area to make a spherical surface compared to any other shape so that it feels minimum surface tension and thus acquire minimum potential energy.

since h = 2S​/Rρg

In artificial satellite, there is a state of weightlessness g=0

∴ h = ∞, But there will be no overflowing of water in tube and water stands up to maximum height in tube available with new surface of higher radius of curvature.

It is to remembered that at critical temperature all three phases of liquid are at equilibrium and the surface tension is zero at this temperature.

When we observe capillary action then angle of water with glass will be acute angle i.e. we will observe a concave meniscus.

When a soap bubble is charged then it expands to decrease the surface Tension, i.e. to minimize the surface tension.

Adding salt to water will increases the surface tension of water. The strong interactions between the sodium cations and the partial negative oxygen, and the chloride anions and the partial positive hydrogen's, although they disrupt part of the hydrogen bonding that takes place between water molecules, actually strengthen the surface tension of water.

when a drop of oil is placed on the surface of water, It will spread as a thin layer because the force of adhesion between water molecules and oils molecules dominates the force of cohesion between oil molecules.