Viscosity coefficient of water

Assuming the hemoglobin molecule to be spherical, calculate its effective radius. The viscosity coefficient of water at this temperature is equal to 1.002 x 10 kg m s . Solution... 

Exercise.—Taking the value in absolute (C.G.S.) units of the viscosity coefficient of water at 25 as equal to 8 9S X io, calculate the value of the viscosity coefficient of benzene at 10°, 20°, 30°, 40°, 50 the values of the relative viscosity to be read from the smoothed curve obtained in the preceding experiment. Compare the results with the following values —... 

Self diffusion coefficients can be obtained from the rate of diffusion of isotopically labeled solvent molecules as well as from nuclear magnetic resonance band widths. The self-diffusion coefficient of water at 25°C is D= 2.27 x 10-5 cm2 s 1, and that of heavy water, D20, is 1.87 x 10-5 cm2 s 1. Values for many solvents at 25 °C, in 10-5 cm2 s 1, are shown in Table 3.9. The diffusion coefficient for all solvents depends strongly on the temperature, similarly to the viscosity, following an Arrhenius-type expression D=Ad exp( AEq/RT). In fact, for solvents that can be described as being globular (see above), the Stokes-Einstein expression holds ... 

If the hydroxonium ions migrated only hydrodynam-ically A° 85 cm2 would be expected, which value can easily be derived by using the -> Stokes law and the known values of the -+ self-diffusion coefficient of water, the radius of the ion and the - viscosity. (See also proton, - Eigen complexes, - Zundel complexes, charge transfer, - Dahms-Ruff theory.)... 

At high solute concentration and low temperature, the viscosity of the system may be greatly enhanced, whereby the diffusion coefficient of water is reduced. Diffusion limitation may now occur. 

The magnitude of the apparent diffusion coefficient of water in rubber is much lower than would be expected from the viscosity of water assuming that it behaved in the same way as... 

It was estimated that the permeability coefficient A( = (1.4 - 4.6)xl0" m/s in the seriously weathered and fractured zone. The distribution of fractures dominates the penetrability of rock mass in the slightly weathered zone, and excavation caused unloading also plays an important role. Parameters concerned (Zhu and Zhang, 1996) are as follows the initial aperture of fractures b = 0. Imm, the dynamical viscosity coefficients of underground water ti = lOxlO m/s, the unit volume discharge s = 6.4xio m /(m s)and the bulk dense of watery = l.OxlO kg/m ... 

Where Z) and are the diffusion coefficient (cm s) and viscosity (poise) of water in these channels. 

HjO = hydraulic permeability coefficient of water M-H20 = dynamic viscosity of water... 

Fraction of water generation that transports through the anode electrode toward the anode channel Permeability of porous media Electrokinetic permeability Membrane permeability due to pressure gradient Hydraulic permeability coefficient of water Dynamic viscosity, fuel cell efficiency... 

The Ostwald type can be purchased from a variety of supply houses with different diameter bores. Small bores are used for a low-viscosity range near that of water and larger bores for more viscous liquids. In order to measure the viscosity coefficient of liquids such as motor oil or molasses. 

This expression gives the viscosity of the second liquid relatively to that of the first. For many purposes only the relative viscosity of a liquid is required, and as comparison viscosity that of water at some particular temperature, either 0° or 25°, is generally chosen. It is, of course, easy to obtain the coefficient of viscosity of a liquid in absolute units, by substituting in the above equation the value in absolute units of iji, the coefficient of viscosity of the comparison liquid. 

For example, the definition of a system as 10.0 g FI2O at 10.0°C at an applied pressure p= 1.00 atm is sufficient to specify that the water is liquid and that its other properties (energy, density, refractive index, even non-thennodynamic properties like the coefficients of viscosity and themial condnctivify) are uniquely fixed. 

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