Blink your eyes and it’s long gone. Carbonic acid exists for only a tiny fraction of a second when carbon dioxide gas dissolves in water before changing into a mix of protons and bicarbonate anions.
Despite its short life, however, carbonic acid imparts a lasting impact on Earth’s atmosphere and geology, as well as on the human body.
However, because of its short lifespan, the detailed chemistry of carbonic acid has long been veiled in mystery. Researchers with Berkeley Lab and the University of California (UC) Berkeley are helping to lift this veil through a series of unique experiments. In their latest study, they’ve shown how gaseous carbon dioxide molecules are solvated by water to initiate the proton transfer chemistry that produces carbonic acid and bicarbonate.
‘Through a combination of X-ray absorption spectroscopy (XAS), theoretical modeling and computational simulations, we’re able to report the first detailed characterization of the hydration structure of carbon dioxide gas dissolved in water,’ says Richard Saykally, a chemist with Berkeley Lab’s Chemical Sciences Division and professor of chemistry at UC Berkeley who leads this research. ‘Our results will help improve future theoretical modeling of this crucial chemistry by characterizing the initial state of the proton transfer reactions that occur in water.