Question

Calculate the value of D at 705°C for the diffusion of some species in a metal for which the values of D0 and Qd are 4.5 × 10-5 m2/s and 164 kJ/mol, respectively.

Answer 1

Answer:

The value of D is $7.753\times10^{-14}\ m^2/s$

Explanation:

Given that,

Temperature = 705°C

Maximum diffusion $D_{0}=4.5\times10^{-5}\ m^2/s$

Activation energy $Q_{d} = 164 kJ/mol$

We need to calculate the value of D

Using formula of diffusion coefficient

$D=D_{0}\ exp\ (\dfrac{-Q_{d}}{RT})$

Where, D = diffusion coefficient

$D_{0}$ = Maximum diffusion coefficient

$Q_{d}$ = Activation energy

T = temperature

R = Gas constant

Put the value into the formula

$D=4.5\times10^{-5}\ exp\ (\dfrac{-164\times10^{3}}{8.31\times705+273})$

$D=7.753\times10^{-14}\ m^2/s$

Hence, The value of D is $7.753\times10^{-14}\ m^2/s$