What are the practical applications of nanoparticles called colloids?
A colloid is a chemical mixture in which one component (the dispersed or internal phase) is in the form of droplets or particles suspended in and distributed evenly throughout the second component (the continuous phase or dispersion medium). The dispersed-phase particle size range in colloids (1-1000 nm) does overlap the size range of nanoparticles (1-100 nm), so some colloids do consist of nanoparticles suspended in a dispersion medium. Some common colloids which may include nanoparticles include inks and colored glass (red glass gets its color from the gold nanoparticles suspended in it).