LOVE LOVEFOOD SCIENCE 02: producing sugar LOVE FOOD LOVE SCIENCE: Light-producing sugar What you need: • sugar cubes • pliers • a very, very dark room What to do: For this experiment, you will be crushing sugar in the dark • Place your pliers and lumps of sugar where you can easily find them in the dark (it may even be worthwhile to practice crushing sugar before you switch off the ) • Turn off the light and wait at least two minutes – be patient, your eyes need time to adjust to the 02 darkness • Carefully crush a lump of sugar in your pliers • Watch carefully... What you may notice: Hopefully, you should see little flashes of blue light as you crush the sugar

The science behind it all: The phenomenon you This energy builds and builds are witnessing is called until you let it go and the rubber Beyond the science: triboluminescence. band shoots back, releasing all When you crush a lump of the energy that it took to stretch Triboluminescence is alteration of sugar, you are fracturing sugar it in the first place. This is very related to , distribution when the . Although the sugar similar to what’s happening with the ability of certain materials is squeezed or stretched. form an orderly the sugar crystals. to produce electricity when Asymmetric, piezoelectric arrangement, the crystals are under mechanical stress materials are more likely to slightly asymmetric. This allows When the two charges (squeezed, rubbed, etc) due be triboluminescent than positive and negative charges to eventually shoot back together to the separation of positive symmetric ones. However, separate from each other as the again, all the energy used to and negative charges. These about a third of known cracks. separate them is released materials use vibration from triboluminescent materials are and they rip through the air to movement to generate not piezoelectric and some First and foremost, crushing reunite. As they do this, they electricity and can also piezoelectric materials are not sugar involves energy. The act are bumping into and exciting change their shape if an triboluminescent. Scientists of simply separating the positive nitrogen molecules in the air, electric voltage is applied. are still trying to figure out and negative charges takes quite causing some of the energy Piezoelectric materials what special characteristic a lot of energy – much like pulling to be released in the form generally have an asymmetric determines whether or not a two magnets apart. Think about of visible light. Think about shape, allowing for the material is triboluminescent. a rubber band – a rubber band triboluminescence as lightning stores energy as you stretch it. occurring on a smaller scale.