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What Do You Mean By “Surface Tension” Of A Liquid?
Surface Tension: On account of the cohesive forces between the molecules of a liquid the free surface of a liquid always behaves like stretched membrane or sheet and tends to contract to the smallest possible area. Let us imagine a line AB drawn on the surface of the liquid. On account of the contractile tendency…
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What Is Surface Energy? Derive The Relation Between The Surface Tension And Surface Energy.
Surface Energy: Due to the surface tension of the liquid, the surface of the liquid tends to decrease the surface area. Hence when the area of a liquid surface is increased, work is done against the surface tension. This work is stored on the surface of the liquid and it is known as the surface…
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Discuss The Effect Of Temperature On Surface Tension.
Effect of temperature: The surface tension of all liquids decreases linearly with rising temperature, over small temperature ranges, so that surface tension at C is given by, where, is the temperature coefficient of surface tension, is the value of surface tension at C. At the critical temperature, the value of surface tension is zero, there…
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Discuss The Effect Of Presence Of Dissolved Substance In The Liquid and Contamination Of Liquid Surface.
Presence of dissolved substances in the liquid: The presence of any foreign substances in the form of solutes in a liquid, changes or affects the surface tension of that liquid differently. Most organic substances when dissolved reduce the surface tension, on the other hand, inorganic substances when dissolved increase the surface tension, increasing linearly with…
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Discuss The Condition Of equilibrium Of A Soap Bubble And Determine The Expression Of “Excess Pressure” Inside It.
Let us consider a soap bubble is produced from a straw as shown in the adjoining Fig.1, as it moves far the size of the soap bubble increases and ultimately takes a particular size when equilibrium condition is reached. When the soap bubble is grown, the inside pressure of the soap bubble is greater than…
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Derive An Expression For The Excess Pressure Inside A Curved Liquid Membrane. Hence Find The Condition Of Equilibrium Of A Soap Bubble.
Excess Pressure Inside A Curved Membrane: Let us consider, there is a curved liquid surface. This surface is at rest. There are two pressures acting on it. One is inward pressure due to the surface tension and the other is outward pressure. This inward pressure is balanced by that equal outward pressure. To find the…
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Define Angle Of Contact.
Angle of contact: Let us consider, a glass plate is dipped vertically inside a liquid and the liquid wets the plate, as in case of water, alcohol, etc. The level of liquid rises up a little along the side of the plate as shown in the adjoining Fig.1. On the other hand, when a glass…
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Upon What Factors Does The Angle Of Contact Depend?
The angle of contact between a liquid and a solid surface depends upon the nature of the solid and the liquid, the medium above the free surface of the liquid. The angle of contact does not depend upon the angle of inclination of the solid to the free surface of the liquid, within which the…
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Show With The Help Of Diagrams How A Liquid Surface Meets A Solid When The Angle Of Contact Is (i) Smaller Than 90 Degree, (ii) Greater Than 90 Degree.
To find whether the angle of contact between a solid and a liquid is obtuse or acute, let us consider the case of a solid, liquid and air in contact. Let θ be the angle of contact and be the surface tension of the air-liquid interface, be the surface tension of the air-solid interface and be the surface tension…
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What Is Capillarity? What Is Capillary Curve?
Capillarity: Capillarity is defined as the phenomenon of ascent or descent of a liquid or elevation or depression of a liquid inside a capillary tube from the level of liquid outside the tube, when the tube is vertically and partially dipped inside the liquid. Let us consider, a capillary glass tube is dipped in a…
