Ab 29.

What is the diffusion coefficient of a membrane-bound protein of molar mass 79,300 daltons at 37°C if the viscosity of the membrane is 1 poise (0.10 N-s-m-2)? Assume that this protein is an unhydrated, rigid sphere that has a density of 1.4 g-cm-3. 4.0 8.05e-12 x m².s-1 What is the average distance traveled by this protein in 2.3 s? 4.0 6.085e-6 x Å

The temperature of a chemical reaction increased 3 fold, therefore the diffusion coefficient of the solute in the reaction (hint: Stokes-Einstein equation) decreased 3 fold increased 3 fold decreased 9 fold increased 9 fold

a) Determine the diffusion coefficient for urea (CH4N20 - molecular weight 60.06 g/mol) dissolved in water at 37 °C. The viscosity of water at 37 °C is 0.6913 *103 Kg, kg and the density of urea is 1.32 g/cm2. m*s The experimental value for the diffusion coefficient is 1.67 109 m2/s. What approximation in your calculation could account for the difference between your computed value and the experimental value for b) the diffusion coefficient?

Estimate the diffusion coefficient for chloroform in air at 25 °C using Boltzmann's equation. If the reported value (of chloroform diffusivity in air at 25 °C air) is 9.5 X 10-2 cm²/s, what is the % error?

The diffusion constant for the amino acid glycine in water is 1.06 × 10⁹ m²/s. In a 2.0-cm-long tube with a cross-sectional area of 1.8 x 10-4 m², the mass rate of diffusion is m/t = 4.2 x 10-14 kg/s, because the glycine concentration is maintained at a value of 8.7 x 10-³ kg/m³ at one end of the tube and at a lower value at the other end. What is the lower concentration?

Estimate the diffusion coefficients and the effective hydrodynamic radii of the alkali metal cations in water from their mobilities at 25 °C (refer to the Resource section for values of the mobilities). Estimate the approximate number of water molecules that are dragged along by the cations. Ionic radii are given Table 15C.2.

40.  Which of the following affects the sedimentation of a particle in gradient ultracentrifugation?  Group of answer choices the affinity of the particle for the gradient solution the viscosity of the particle solution the total mass of the gradient and tube the density of the gradient solution the number of hydrophobic residues

10. The diffusion rate for a solute is 4.0 x 10-1" kg/s in a solvent- filled channel that has a cross-sectional area of 0.50 cm² and a length of 0.25 cm. What would be the diffusion rate m/t in a channel with a cross- sectional area of 0.30 cm² and a length of 0.10 cm?

Calculate the diffusion constant of nitrogen at 20.0 ̊C and 100.0 Pa, with  = 0.43 nm^2 .

Organic chemistry

7. The sedimentation and diffusion coefficients for myoglobin in dilute aqueous solution at 20°C are 2.04 x 10-13 s and 1.13 x 10-10 m²s¹, respectively. The partial specific volume of the protein is 0.741 cm3g-1, the density of the solution is 1.00 x 10-3 gcm³ and the coefficient of viscosity of the solution is 1.00 × 103 kgm 1s¹. Calculate (a) the relative molecular mass and (b) the frictional ratio of this protein. What is the probable shape of a dissolved myoglobin molecule? U n

Q(3): Figure below shows a plot of the logarithm (to the base 10) of the diffusion coefficient versus reciprocal of absolute temperature for the diffusion of carbon in iron (a-Fe). Determine values for the activation energy and the preexponential? 10-10 C in a-Fe 10-12 10-14 10-16 10-18 0.5 1.0 1.5 Reciprocal temperature (1000/K) Diffusion coefficient (m2/s)

For drive-in diffusion of boron in silicon at Tad = 1373 K (drive-in diffusion temperature), determine the drive-in diffusion time ta if the junction depth is 3 μm. Let Qo 3.0 × 1018 atoms/m², CB = 0.85 x 1020 atoms/m³. For diffusion, let Qa 3.75 eV/atom and Do = 2.4 × 10-3 m²/s. =

η helium = 1.88 x 10-5 Pa s at 0 C, calculate the diffusion coefficient and the thermal conductivity coefficient.

Calculate the diffusion constant of argon at 25 °C and (a) 1 Pa, (b) 100 kPa and (c) 10 MPa.

At 25 °C the molar ionic conductivities of Li+, Na+, and K+ are 3.87 mS m2 mol−1, 5.01 mS m2 mol−1, and 7.35 mS m2 mol−1, respectively. What are their mobilities?

4. Estimate the effective radius of a sucrose molecule in water at 25°C given that its diffusion coefficient is 5.2 x 10-10m²/s and the viscosity of water is 0.0100P.

Explain the difference between a. nucleation and particle growth b. occlusion and mixed-crystal formation c. precipitation and coprecipitation

The self-diffusion coefficient of radioactive ³H2O in ordinary water (M =18.0×10³ kg mol¬') at 25°C is 2.44 x10~ m² s-!. For ordinary water, the density is 0.997×10³ kg m³, and the viscosity is 0.891×10-3 kg m¯l s-!. What is the collision diameter of ³H2O ?

-10 m² s 6. [15] The diffusion coefficient of sucrose molecule in water is 5.22x107 at 25°C. How long does it take for a sucrose molecule to diffuse a) 1 mm, b) 1 cm, c) 1 m from its starting point in a sample of unstirred water? What is the flux of the sucrose molecules down a concentration gradient of 0.1 mol L-¹ m² ¹?

The mobility of a NO3− ion in aqueous solution at 25 °C is 7.40 × 10−8 m2 s−1 V−1. Calculate its diffusion coefficient in water at 25 °C.  Options: a) 1.09E-9 b) 1.90E-9 c) 3.05E-9

The volume of O2(g) adsorbed on a surface of 1 g of a silica sample at 5°C is V1=1.4 cm3 at P1=95.1 torr and V2=10.6 cm3 at P2=760 torr. Identify the maximum volume of oxygen, Vm, that can be adsorbed. Consider the Langmuir isotherm model