When a gas bubble in a liquid is excited by ultrasonic acoustic waves, it can emit short flashes of light suggestive of extreme temperatures inside the bubble. These flashes of light, known as 'sonoluminescence', occur as the bubble implodes, or cavitates. Now Didenko and Suslick show that chemical reactions occur during cavitation of a single, isolated bubble,and they go on to determine the yield of photons, radicals, and ions formed. (Photo credit: Kenneth S. Suslick and Kenneth J. Kolbeck)

Didenko, Y.; Suslick, K. S. "The Energy Efficiency of Formation of Photons, Radicals, and Ions During Single Bubble Cavitation" Nature 2002, 418, 394-397.