It might be weird to think about molecules as expressing “handedness.” After all, molecules don’t have hands. But there is a class of organic molecules known as chiral molecules that can be thought of as being either left-handed or right-handed, similar to the way we favor one appendage over the other.
Basically, chiral molecules with different handedness will share the same chemical structure, but with different geometries. They’re essentially arranged as mirrors of one another, in such a way that they’re non-superposable. So it’s impossible to flip one to make it match the other.
“When you shake somebody’s hand, your right hand shakes another right hand, and it forms that nice, interlocking gesture; if you try to shake a left hand with your right hand it’s a little awkward because the interaction is different,” explained Brett McGuire, a researcher at the National Radio Astronomy Observatory in Virginia. “Chiral molecules work the same way.”
Published by Mother Nature Network. See more at: http://www.mnn.com/earth-matters/space/stories/twisty-molecules-handedness-are-essential-life-found-deep-space
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