liquid2 - Viscosity of liquids Viscosity is defined as the...

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Viscosity of liquids ± Viscosity is defined as the resistance in the flow of a liquid or internal friction present between two layers of a liquid which resists the flow of liquid ± A liquid with high viscosity is thick and flows slowly ± A liquid with low viscosity is thin and flows quickly ± Different liquids have different viscosities ± Viscosity is a characteristic property of all liquids ± Honey flows less readily than water because honey has a higher viscosity than water (honey is more viscous than is water).
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Measurement of viscosity ± Viscosity is measured by determining the rate at which a liquid flows through a small- diameter glass tube . ± In 1844 Jean Louis Marie Poiseuille showed that the volume of fluid ( V ) that flows down a small-diameter capillary tube per unit of time ( t ) is proportional to the radius of the tube ( r ), the pressure pushing the fluid down the tube ( P ), the length of the tube ( l ), and the viscosity of the fluid ( η ). Viscometers
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Viscosity ± Viscosity is reported in units called poise (pronounced "pwahz"). ± The viscosity of water at room temperature is roughly 1 centipoise , or 1 cP. ± Gasoline has a viscosity between 0.4 and 0.5 cP ± The SI units (International System of Unit) of viscosity are newton-second per meter squared (N s / m 2 )
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FACTORS AFFECTING VISCOSITY ± Size of molecules Viscosity of a liquid having large molecules is high whereas the viscosity of those liquids that have small molecules is low. ± Shape of molecules Spherical molecules provide resistance, but oval shaped or disc like molecules provide greater resistance in the flow of liquid. That’s why viscosity of liquids having spherical molecules is low.
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FACTORS AFFECTING VISCOSITY ± Intermolecular forces Liquids having large intermolecular forces have greater viscosity. ± Temperature Viscosity of liquid decreases with increase in temperature. Because an increase in temperature, reduces the forces of attraction between molecules.
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liquid2 - Viscosity of liquids Viscosity is defined as the...

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