Presented By: Department of Chemistry
Gomberg Lecture with Gil Nathanson "Big Atmosphere, Little Droplets, Tiny Atoms: What Can Helium Atoms Teach Us About Sea Spray?"
Gil Nathanson (University of Wisconsin–Madison)
Sea spray droplets are complex beasts that contain surface-active organic molecules in addition to water and salts. These aerosol particles behave like little chemical laboratories that transform gases in the atmosphere and alter the concentration of key species, including ozone, the hydroxyl radical, and methane. But what do helium atoms have to with aerosols? Amazingly, when helium atoms are dissolved in sea spray proxies, they evaporate at super-Maxwellian speeds that vary sensitively with the identity of the salts and surfactants in solution. The excess helium kinetic energies teach us about the interfacial morphologies of surfactant-salt-water solutions, which we can explain using two beautiful chemical concepts: the principle of detailed balance and potentials of mean force. We can use what we have learned to discuss how charged surfactants can significantly alter the outcome of reactions in sea spray because they control the segregation of reactive ions to the surface. Just a speck of surfactant goes a long way!
This talk will include some fun hands-on soapy water activities at your seat. Please bring your water bottle if you have one.
This talk will include some fun hands-on soapy water activities at your seat. Please bring your water bottle if you have one.