Teaching NVS Junior Secretariat Assistant (JSA) Mock Test 2024 General Science Physics Surface Tension
Comprehension Passage
Read the Paragraph carefully and answer the following questions.
Surface tension is indeed a property of the liquid surface that makes it behave somewhat like an elastic sheet. This is primarily due to the cohesive forces between the molecules in the liquid, which are especially noticeable at the surface. When the temperature of a liquid increases, the kinetic energy of its molecules also increases. This enhanced movement reduces the effectiveness of the cohesive forces holding the molecules together. As a result, the surface tension of the liquid decreases. One reason why hot water is more effective for washing clothes is indeed due to the lower surface tension of hot water. This lower surface tension allows the water to more readily penetrate the fibers of the clothing and dissolve or loosen dirt and grease. he presence of certain impurities in water can decrease its surface tension. This is often the basis for the action of soaps and detergents, which contain substances (surfactants) that can decrease the surface tension of water.
Surface tension is indeed a property of the liquid surface that makes it behave somewhat like an elastic sheet. This is primarily due to the cohesive forces between the molecules in the liquid, which are especially noticeable at the surface. When the temperature of a liquid increases, the kinetic energy of its molecules also increases. This enhanced movement reduces the effectiveness of the cohesive forces holding the molecules together. As a result, the surface tension of the liquid decreases. One reason why hot water is more effective for washing clothes is indeed due to the lower surface tension of hot water. This lower surface tension allows the water to more readily penetrate the fibers of the clothing and dissolve or loosen dirt and grease. he presence of certain impurities in water can decrease its surface tension. This is often the basis for the action of soaps and detergents, which contain substances (surfactants) that can decrease the surface tension of water.
Which of the following statement is correct related to the Surface tension?
1
It is the tension of the surface film of a liquid caused due to the attraction of the particles in the surface layer by the bulk of the liquid, which tends to maximize surface area.
2
When impurities are added to the water the intermolecular distance decreases due to which Van der Wall forces increase.
3
When impurities are dissolved in water, the surface tension of water increases.
4
When impurities are dissolved in water, the surface tension of water decreases.