ceutics Exam 3

Boundary between two phases

Interfaces

if the boundary is between a gas and liquid or a gas and solid it is typically called a _____

Surface

the result of inward attractive pull of surface molecules toward the bulk and a contraction of the surface results in a ____

Surface tension

The force per unit length that exists between two immiscible liquid phases

Interfacial tension

Which statement best describes the relationship between interfacial tension and the interactions between two immiscible liquid phases?

Interfacial tension decreases as adhesive forces between the phases increase, leading to less repulsion.

This lowers the contact angle between a liquid and solid by replacing the air over the solid surface with liquid

Wetting agent

In order to make things wet, we need to do what

Lower the angle of contact

Surface active agents are also called

Surfactants

Where do surfactants accumulate

At the boundary between two phases

Surface molecules are characterized by having a discrete region of hydrophobic and hydrophilic groups

Amphiphiles

This term denotes a molecule’s affinity for both polar and non-polar environments

Amphiphilic