Sage-Tips

What is the mathematical expression of surface tension?

Surface tension is defined as, The ratio of the surface force F to the length L along which the force acts. Mathematically, surface tension can be expressed as follows: T=F/L.

What is the relationship between surface tension and polarity?

Because of their polarity, water molecules are strongly attracted to one another, which gives water a high surface tension. The molecules at the surface of the water “stick together” to form a type of ‘skin’ on the water, strong enough to support very light objects.

What is the relation between concentration and surface tension?

The observed values shows that surface tension is inversely proportional to the concentration as shown in figure 4. Hence, study shows that surface tension decreases as we increase the concentration of gum solution.

What is directly proportional to surface tension?

The extent of the rise (or fall) is directly proportional to the surface tension of the liquid and inversely proportional to the density of the liquid and the radius of the tube.

How is surface tension measured experimentally by drop number method?

‘drop’) is one of the most common methods for measuring surface tension. The principle is to measure the weight of drops of a fluid of interest falling from a capillary glass tube, and thereby calculate the surface tension of the fluid. We can determine the weight of the falling drops by counting them.

Does surface tension depend on surface area?

No, surface tension doesn’t depend on the surface area. The surface tension primarily depends on the forces of attraction between the particles within the giving liquid and also on the gas, solid or liquid in contact with it.

What is the relationship between surface tension and drop diameter?

It is concluded that surface tension can be expected to decrease with decrease in droplet size over a wide range of circumstances. In addition, approximate figures are obtained for the rate at which such decreases may be expected. The decreases become significant for very small drops.

What are factors affecting surface tension?

Surface tension is caused by the effects of intermolecular forces at the interface. Surface tension depends on the nature of the liquid, the surrounding environment and temperature. Liquids where molecules have large attractive intermolecular force will have a large surface tension.

How does surface tension vary with concentration of sugar solution?

\%, the surface tension of the aqueous solutions of dextrose and fructose decreases continuously with increasing concentration (the effect is more pronounced for dextrose). Then, the surface tension increases above the surface tension of water (similar to sucrose solutions) for higher concentrations.

What is the relationship between surface tension and temperature?

The strength of surface tension depends on intermolecular forces. As temperature increases, molecules of liquid become more active and they move more rapidly; therefore, the intermolecular forces are more instable. Surface tension decreases with increasing temperature.

How surface tension is related to density and number of drops?

The ratio of any two drop volumes is almost equal to the ratio of the corresponding surface tension values.

What is the surface tension of a solution?

Surface tension of solutions In the case of solutions, contrary to pure liquids, simultaneously with the changes of surface area,the surface tension γ may change. If a two-component solution behaves as a regular one,its surface tension changes as a function of the surface composition, according to the equation derived by Prigogine and Defay.

Is surface tension related to intermolecular forces?

Since the surface tension is a manifestation of intermolecular forces, it may be expected to be related to other properties derived from intermolecular forces, such as work of cohesion internal pressure, and compressibility. 1) Relationship between work of cohesion and surface tension (Grunberg 1949)

How do you measure surface energy and surface tension?

Contaminants on the surface reduce the net inward force and decrease surface energy. The surface energy of solids can be measured by fracture and indentation techniques. The surface tension in liquids can be measured by using wire frames. The angle of contact is the angle through the liquid to the solid.

How reliable are the values of polar factors for surface tension?

However, the general reliability was not known; the values of polar factors are available for only a few substances and estimated values of the surface tension σ are sensitive to the value of the chosen polar factor (Reid et al., 1987; Poling et al., 2001).