A liquid drop of a sodium-potassium alloy deposited on water starts reacting to produce alkali metal hydroxide, hydrogen, and heat. Solvated electrons turn the drop blue and then black. Subsequently, the drop turns blue again and then red as the drop heats enough for the metals to evaporate. Finally, the metal vapor clears and the drop’s temperature falls as it transformes into transparent molten alkali metal hydroxides before dropping into the water and bursting as the two materials mix. Credit: Angew. Chem. Int. Ed. Engl.