Why the viscosity of a liquid decreases while that of a gas increases with an increase of temperature?
The increase in temperature causes the kinetic or thermal energy to increase and the molecules become more mobile. The attractive binding energy is reduced and therefore the viscosity is reduced.
Why does viscosity of liquids increase with temperature?
When a liquid is heated, the kinetic energy of its molecules increases and the intermolecular attraction becomes weaker. Hence, the viscosity of a liquid decreases with increase in its temperature.
How does viscosity of gases change with temperature?
The viscosity of liquids decreases rapidly with an increase in temperature, and the viscosity of gases increases with an increase in temperature. Thus, upon heating, liquids flow more easily, whereas gases flow more sluggishly.
Why does viscosity of liquid increase with pressure?
Based exclusively on very general considerations concerning the relationship between viscosity and “free volume,” we show that, at moderate values of pressure, viscosity increases, as a rule, with increasing pressure, provided the liquid is in stable or metastable (undercooled) equilibrium states.
How does the co efficient of viscosity of a liquid depend on temperature and pressure?
Experiments have shown that the coefficient of viscosity of liquids decreases with increasing temperature, while the coefficient of viscosity of gases increases with increasing temperature. A striking result of the kinetic theory of gases is that the viscosity of a gas is independent of the density of a gas.
How does viscosity vary with temperature and pressure?
The shear viscosity of the liquids that are used as lubricants increases with increasing pressure and decreases with increasing temperature and, at sufficiently large stress (rate), decreases with increasing shear stress (shear rate). …
What is the effect of temperature and pressure on surface tension?
As the temperature increases, viscosity decreases. Surface tension decreases with increase in the temperature. So these, are the effects of temperature on viscosity and surface tension.
Does liquid viscosity increase with temperature?
The liquid viscosity is highly affected by the heat. The viscosity decreases with an increase in temperature. Most liquids suffer the exponential relationship (Seeton, 2006) between temperature and viscosity rather than linear form (Fig. 6.1).
How does temperature affect viscosity of a liquid experiment?
The viscosity of each liquid tested was found to be dependent on the temperature of the liquid. As the temperature of the liquid rises, my experiment showed that the viscosity of the liquid goes down. As the temperature of the liquid goes down, the viscosity of the liquid goes up.
What is the most important factor when it comes to viscosity of liquids?
Temperature has a major effect on viscosity; the viscosity decreasing significantly with increase in temperature. As the temperature increases the molecules in the liquid move about more, and therefore spend less time in contact with each other, thus the internal friction of the liquid decreases.
What are 3 factors that affect viscosity?
3.2 FACTORS AFFECTING VISCOSITY The viscosity of Newtonian fluids is affected by temperature, pressure, and, in the case of solutions and mixtures, by composition.
What is viscosity and the factors that affect it?
What factors affect viscosity? Viscosity is resistance to flow. For liquids, typically the larger the intermolecular forces (IMF) the higher the viscosity. The other factors that affect viscosity are temperature and the shape of the molecule.
What are the factors that affect flow rate?
Factors that affect fluid flow
- The viscosity, density, and velocity of the fluid.
- Changes in the fluid temperature will change the viscosity & density of the fluid.
- The length, inner diameter, and in the case of turbulent flow, the internal roughness of the pipe.