Marangoni instability from picolitre sessile droplets —

What if a picolitre ethanol drop hits a thin water film of a few microns? High speed camera caught the moment of drop impact: water film is contracted into a drop and repelled, whereas ethanol drop spreads with the development of the fingering instability at the nearside of water droplet.

https://downloads.sms.cam.ac.uk/2877155/2877162.mp4