What is Molecular Chirality?
What is Molecular Chirality? "The term chirality (pronounced ky-RAL-it-ee) comes from the Greek word cheir, meaning "hand." In chemistry, a molecule is considered chiral if it cannot be superimposed (perfectly aligned or stacked) onto its mirror image. The easiest way to understand this is the "hands" analogy. Your left and right hands are exact mirror images of each other. However, no matter how you turn or rotate them, you cannot stack them palm-to-palm or back-to-back so that all your fingers match up perfectly in 3D space. If a molecule has this same "handedness," it is chiral. If a molecule can be perfectly aligned with its mirror image (like a perfectly round ball or a plain coffee mug), it is called achiral (not chiral). What Makes a Molecule Chiral? For a molecule to be chiral, it must lack an internal plane of symmetry. In organic chemistry, the most common cause of chirality is a chiral center (also called a stereocenter). This occurs when a...