Observing chirality and the ‘handedness’ of sugar
Find out more about the molecular property of chirality and try a simple experiment using sucrose to explore ‘handedness’ of sugar yourself.
The first inkling of the existence of a molecular property called chirality came in 1832 when French scientist Jean-Baptiste Biot observed that solutions of tartaric acid crystals were able to rotate the plane of polarised light. Tartaric acid is responsible for some of the tartness in wine and its crystals can sometimes be found on wine corks.
Then in 1847 French chemist Louis Pasteur noted the difference in optical activity between two chemically identical compounds: tartaric acid, which was optically active, and paratartaric acid (also known as racemic tartaric acid), which was not. An optically active material is able to rotate the plane of polarised light.
Read on to investigate this property yourself using a solution of sucrose and a pair of sunglasses.
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