Water can form interesting ice crystals on surfaces that separate warm and cold air, like this porch window in Rochester, NY. Water first froze into dendrites, then some of it thawed to form droplets. Those droplets then refroze to form smaller dendrites on the surface of the droplets.
Submitted by Paul Schwartz
Chemistry in Pictures is accepting entries to its water-themed contest until July 3. Enter today!
Do science. Take pictures. Win money. Enter our photo contest here.
Related C&EN Content: