What causes this intense reaction that makes me wanna cry like a new born......Thanks for your extra bit o' detail....Tom Science 4
2007-01-21 04:17:58 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Botany
Sulphur Dioxide fumes/gas. Cutting the onions releases sulphur dioxide from the cells of the onions. The sulphur dioxide reacts with water to produce sulphuric acid.
Picture the sulphur dioxide gas getting to the water in your eyes. At that moment, your tears are becoming more and more acidic and irritating your eyes to produce more water/tears which reacts with more sulphur dioxide to form more sulphuric acid.
I use a fan to blow the sulphur dioxide away or chop the onions in water to reduce the effects, if needed.
2007-01-21 04:20:49 · answer #1 · answered by Gary D 7 · 1⤊ 0⤋
As onions are sliced, cells are broken open. Onion cells have two sections, one with enzymes called alliinases, the other with sulfides (amino acid sulphoxides). The enzymes break down the sulphides and generate sulphenic acids. Sulphenic acids are unstable and decompose into a volatile gas called syn-propanethial-S-oxide. The gas then dissipates through the air and eventually reaches one's eye, where it will react with the water to form a dilute solution of sulphuric acid. The sulphuric acid irritates the nerve endings in the eyes, making them sting. The tear glands then produce tears to dilute and flush out the irritant.
A firm in Toronto, Canada, attempted to utilize this property of onions in the manufacture of a form of tear gas for civilian use. It was marketed in 1991 but was unsuccessful as it had an effective shelf life of only three months.
Supplying ample water to the reaction prevents the gas from reaching the eyes. Therefore cutting the onions under running tap water or completely under water can help, as can rinsing the onion and leaving it wet while cutting. Chilling the onion will prevent the enzymes from activating, which will limit the amount of gas generated. Some people will freeze their knives to enhance this effect. Finally, using a sharp knife will limit the cell damage, and therefore prevent the release of enzymes.
Different species of onions will release different amounts of sulphenic acids, thus some will cause more tear formation and irritation than others.
The characteristic odor of onions can be removed with lemon.
2007-01-21 04:26:51 · answer #2 · answered by Mikhil M 2 · 0⤊ 0⤋
Onions have a chemical in them that causes your eyes to tear up,duh!!!
2007-01-21 04:21:29 · answer #3 · answered by Jackie H. 2 · 0⤊ 1⤋
because you dint peel them under cold running water
2007-01-21 04:22:35 · answer #4 · answered by Bertie D 4 · 0⤊ 1⤋
run the cold water while you cut them,then you won't cry!
2007-01-21 04:22:46 · answer #5 · answered by ken 4 · 0⤊ 1⤋
because of the sulfur it contains.
2007-01-21 04:23:55 · answer #6 · answered by َAnnie 1 · 1⤊ 0⤋