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Chemistry In Pictures

Chemistry in Pictures: Midair crystallization

November 17, 2017

A blue droplet is suspended in midair.
Credit: Courtesy of Franziska Emmerling

It’s not magic, it’s acoustic levitation. The two metal probes emit and reflect sound waves that trap this liquid droplet in midair. Franziska Emmerling uses the effect to study crystallization without interference from container walls, which can influence the rate of crystal formation (Cryst. Growth Des. 2014, DOI: 10.1021/cg501287v). “In a typical experiment, we use an under saturated solution of a certain compound,” she says. “During the experiment, solvent evaporates from the droplet and the saturation level increases leading to nucleation and then crystallization.” In this photo, however, they’re just levitating blue ink to demonstrate the apparatus.

Three colorful balloons affixed to a reaction flask in a fume hood.
Credit: Henry Powell-Davies
A well-shot photo of an amber liquid being injected into a sealed round-bottom flask in an ice bath.
Credit: Townsend Lab

Emmerling (@FranEmmerling) submitted this photo as part of the #RealTimeChem photo contest. The two runners-up in the Reactions category were Henry Powell-Davies (@hpowelldavies) with his balloon reaction and the Townsend lab at Vanderbilt (@Townsend_Lab) with this well-composed flask shot.

Do science. Take pictures. Win money. Enter our photo contest here.

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Lab Levitation, How Bubbly Is Bubbly?


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