Skip to main content
5 votes

Convection or Advection term in the Absolute flux of a chemical species

The term advection in transport phenomena is generally introduced in the definition of material derivative of a scalar magnitude $B$ is \begin{equation} \frac{\mathrm{D}B}{\mathrm{D}t} = \...
Metal Storm's user avatar
  • 3,546
4 votes
Accepted

Graham's Law for mixtures?

It depends on the definition of average (strictly speaking on the choice of mean), as there are many types. The expression provided can be rewritten in the form $$M_{avg}^{-1/2} = \chi_A M_A^{-1/2} + \...
Buck Thorn's user avatar
  • 22.5k
2 votes

Smell of orange peel travels super fast

The setup confounds chemistry and physics on side (transport of molecules by ┬źnormal┬╗ air flow because a door/window, sash of a hood is open; convection by a radiator, diffusion by concentration ...
Buttonwood's user avatar
  • 30.1k
2 votes
Accepted

Would microelectrodes reach a steady state current if convection is negligible and only pure diffusion occurs?

Yes. It does reach a steady state. We consider the electrochemical academic reaction $$\ce{O + ne^- <=> R} \tag{R1} $$ to keep things simple, let $C$ be the concentration of species $\ce{O}$. ...
Metal Storm's user avatar
  • 3,546
2 votes
Accepted

How do I express concentration of a substance at the interface between two membranes of different diffusivities and lengths at steady state?

The answer sheet as provided in the textbook indicates that the correct solution is: $$C_i = {{D_\text{A} C_\text{A}\over \Delta x_\text{A}}+{D_\text{B} C_\text{B}\over \Delta x_\text{B}}\over {D_\...
Poutnik's user avatar
  • 42.4k
2 votes
Accepted

If gaseous oxygen and dissolved oxygen (in water) have the same partial pressure, will they diffuse into solid materials at comparable rate?

If the air and water are in equilibrium, then che chemical potential of the oxygen in the air is equal to the chemical potential of the oxygen in the water. If either is placed in contact with your ...
Chet Miller's user avatar
  • 13.5k
1 vote

In steady state diffusion of atoms, does dJ/dt = 0 hold true?

The steady state corresponds to the behaviour of the solutions of the equations of conservation of a physical-chemical system when $t \to \infty$. In practice, depending on the 'inertia' of the ...
Metal Storm's user avatar
  • 3,546

Only top scored, non community-wiki answers of a minimum length are eligible