Determination of variables affecting surface tension

The legs of a water strider are long and slender, allowing the weight of the water strider body to be distributed over a large surface area.

Determination of variables affecting surface tension

Floating a needle: A carefully placed small needle can be made to float on the surface of water even though it is several times as dense as water. Surface tension gives them their near-spherical shape, because a sphere has the smallest possible surface area to volume ratio. This creates some internal pressure and forces liquid surfaces to contract to the minimum area. The legs are strong, but have flexibility that allows the water striders to keep their weight evenly distributed and flow with the water movement. On the other hand, when adhesion dominates adhesion energy more than half of cohesion energy the wetting is high and the similar meniscus is concave as in water in a glass. Due to the surface tension, small objects will "float" on the surface of a fluid, as long as the object cannot break through and separate the top layer of water molecules. Although easily deformed, droplets of water tend to be pulled into a spherical shape by the cohesive forces of the surface layer.

This type of surface tension is called "interface tension", but its chemistry is the same. Thus the surface is under tension, which is probably where the name "surface tension" came from.

explain the factors affecting surface tension with their effect

But if the detergent lowers the surface tension, the heating may be unnecessary. Surface tension disinfectants: Disinfectants are usually solutions of low surface tension.

Explain the factors affecting surface tension with their effect

Consequently, the surface will push back against any curvature in much the same way as a ball pushed uphill will push back to minimize its gravitational potential energy. Causes[ edit ] Diagram of the forces on molecules of a liquid Due to the cohesive forces a molecule is pulled equally in every direction by neighbouring liquid molecules, resulting in a net force of zero. But if the detergent lowers the surface tension, the heating may be unnecessary. The legs of a water strider are long and slender, allowing the weight of the water strider body to be distributed over a large surface area. If the surface is agitated to break up the surface tension, then needle will quickly sink. Source: Lakes of Missouri Within a body of a liquid, a molecule will not experience a net force because the forces by the neighboring molecules all cancel out diagram. Washing with cold water: The major reason for using hot water for washing is that its surface tension is lower and it is a better wetting agent. Tiny fragments of oil suspended in pure water will spontaneously assemble themselves into much larger masses. Although easily deformed, droplets of water tend to be pulled into a spherical shape by the imbalance in cohesive forces of the surface layer. Effects of surface tension[ edit ] Water[ edit ] Several effects of surface tension can be seen with ordinary water: Beading of rain water on a waxy surface, such as a leaf.

Washing with cold water: The major reason for using hot water for washing is that its surface tension is lower and it is a better wetting agent.

The addition of surfactants, however, can have a stabilizing effect on the bubbles see Marangoni effect. Water dripping from a tap C.

Factors affecting viscosity

Those on the surface have no neighboring molecules above and, thus, exhibit stronger attractive forces upon their nearest neighbors on and below the surface. Consequently, the surface will push back against any curvature in much the same way as a ball pushed uphill will push back to minimize its gravitational potential energy. The addition of surfactants, however, can have a stabilizing effect on the bubbles see Marangoni effect. Its cause is a complex interaction between the differing surface tensions of water and ethanol ; it is induced by a combination of surface tension modification of water by ethanol together with ethanol evaporating faster than water. But if the detergent lowers the surface tension, the heating may be unnecessary. It will float on normal urine, but will sink if the surface tension is lowered by the bile. Surface tension and droplets: Surface tension is responsible for the shape of liquid droplets. Due to the surface tension, small objects will "float" on the surface of a fluid, as long as the object cannot break through and separate the top layer of water molecules. Causes[ edit ] Diagram of the forces on molecules of a liquid Due to the cohesive forces a molecule is pulled equally in every direction by neighbouring liquid molecules, resulting in a net force of zero. The molecules at the surface of a glass of water do not have other water molecules on all sides of them and consequently they cohere more strongly to those directly associated with them in this case, next to and below them, but not above.

But if you touch the tent material with your finger, you break the surface tension and the rain will drip through. The molecules at the surface do not have the same molecules on all sides of them and therefore are pulled inward.

Factors affecting surface tension of a liquid

Since any curvature in the surface shape results in greater area, a higher energy will also result. The forces of attraction acting between the molecules of same type are called cohesive forces while those acting between the molecules of different types are called adhesive forces. If a stream of water were running from the faucet, the stream would break up into drops during its fall. On the other hand, when adhesion dominates adhesion energy more than half of cohesion energy the wetting is high and the similar meniscus is concave as in water in a glass. However for a molecule on the surface of the liquid, there will be a net inward force since there will be no attractive force acting from above. Source: GSU. Multimedia Surface tension in water might be good at performing tricks, such as being able to float a paper clip on its surface, but surface tension performs many more duties that are vitally important to the environment and people. It will float on normal urine, but will sink if the surface tension is lowered by the bile. This behavior of the water pushes the water strider upward so it can stand on the surface of the water as long as its mass is small enough that the water can support it. Cohesion and Surface Tension The cohesive forces between molecules in a liquid are shared with all neighboring molecules. When cohesion dominates specifically, cohesion energy is more than double of adhesion energy the wetting is low and the meniscus is convex at a vertical wall as for mercury in a glass container. The addition of surfactants, however, can have a stabilizing effect on the bubbles see Marangoni effect. Due to the surface tension, small objects will "float" on the surface of a fluid, as long as the object cannot break through and separate the top layer of water molecules.
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FACTORS AFFECTING THE SURFACE TENSION OF SOIL SOLUTIONS AND : Soil Science