[dipesh747]

My lecture notes say:

If η_i is the amount of component I in the surface phase σ in excess of that which would have been in
σ had the bulk phases α and β extended to a surface S with unchanging composition then the surface
excess concentration of solute Γι of component I is given by:

Γι = η_i / A

Does anyone know what he is trying to say?

[juanrga]

My lecture notes say:

If η_i is the amount of component I in the surface phase σ in excess of that which would have been in
σ had the bulk phases α and β extended to a surface S with unchanging composition then the surface
excess concentration of solute Γι of component I is given by:

Γι = η_i / A

Does anyone know what he is trying to say?

The excess concentration Γι is given by that expression where A is the area of the surface and η_i ≡ n_i - <n_i>

n_i is the total amount of I and <n_i> is the average value obtained as the volume times the bulk concentration.