Interfacial phenomena

Question 1

Surface tension

Answer 1

The attraction of particles ni a liquid that minimizes the available surface area

Question 2

osmotic pressure

Answer 2

the minimum pressure applied to prevent osmosis through a semipermeable barrier

Question 3

osmosis

Answer 3

when two solutions are separated by a semi permeable membrane, the solvent preferentially move towards the side with higher solute concentration until the concentrations reach equilibrium

Question 4

line tension

Answer 4

interfacial energy at the edge of membrane domain or at the lipid phase separation in cell membrane

Question 5

Gibbs Isotherm

Answer 5

Lets you determine amount of surfactant adsorption based on surface tension and surfactant concetration.

d (surface tension)/d log(surfactant concentration) = -2.303 RT *(surfactant adsorption)

Question 6

Langmuir isotherm

Answer 6

Describes increasing surface occupancy as pressure increases until the surface is coated in a single layer of molecules

(Volume of Gas adsorbeD) = (total volume of gas possible to adsorb)*P/(P+ pressure at which half is adsorbed)

Question 7

how does humidity effect substrate and adsorption?

Answer 7

Humid air causes an additional diffusive layer between the air and substrate such that there are 2 interfaces - air/vapor and vapor/substrate