•High fraction of atoms at or near the surface.
•Surface Tension: liquids surfaces behave as though
they are an elastic film.
•Kelvin Effect: higher vapor pressure over smaller
droplets
•Ostwald Ripening: large particles grow at the
expense of smaller particles
•Adsorption: impurities tend to stick to surfaces
•Surface charge: adsorption of ions can leave the
nanoparticle electrically
charged