Cutting onions is like unleashing a series of chemical reactions. When we cut the onion, the onion molecules transform into a gas that is sulphuric in nature. As soon as this gas comes in contact with our eyes, it transforms into small amounts of sulphuric acid which itches, burns and brings tears to our eyes. The enzymes that are normally locked inside the onion cells, break open as soon as the knife slices through the onion, creating a little molecule that gets into the air. It releases a gas that floats up to the eyes and causes our eyes to water as defence, to flush it out.
Why does chopping onions make you cry?
