In order to predict how chemicals might interact with each other, chemists must get a good understanding of the 3D shapes of molecules. A great way to do this is to study their symmetry.
If you can imagine rotating a molecule (or any 3D object) without changing the way it looks, you have identified some symmetry in the molecule. The same is true if you replace rotations with reflections, or some combination of the two.
In the questions below you will find molecules mixed in with more familiar shapes. In each case, all but one of the objects have exactly the same symmetry. Can you spot the odd one out?
Solutions will be posted online shortly.
Want to know more?
If you would like to find out how chemists describe and classify the symmetry of molecules, this website has more information, including many nice animations and also further symmetry challenges!
Liz Rayment – Chemistry teacher and Deputy Head of Sixth Form at Cheney School, Oxford