Boiling water one bubble at a time Available to Purchase

The first step in boiling water is the formation of bubbles at the bottom of the pan. Those bubbles grow and leave the heated surface within a few milliseconds, which makes it difficult to study their formation in real time. Now Shalabh Maroo of Syracuse University and his colleagues have found a way to make the bubbles stick around longer. They took a container filled with room-temperature water and used a focused laser beam to locally heat a spot at the bottom of the container. A vapor bubble that forms on the spot can be held in place for hours by setting the laser power so that evaporation at the bubble’s base is balanced by condensation at its cooler parts. Thanks to that stability, the researchers could study at leisure how bubbles on a heated surface behave in different situations, including presence or absence of dissolved air, the use of...