Shapes and dynamics of miscible liquid/liquid interfaces in horizontal capillary tubes

► Optical observations of the dissolution behaviour of various binary mixtures. ► Miscible interfaces are endowed with surface tension. ► Interfaces smear due to interdiffusion. ► Glycerol/water and soybean oil/hexane interfaces move due to barodiffusion. ► IBA/water interfaces move due to spontaneous imbibition.