Mirror Planes of Symmetry f If two groups are the same, carbon is achiral (animation KH H · A molecule with an internal mirror CI CI plane cannot be Internal mirror plane chiral of symmetry(σ) Caution! If there is no plane of symmetry, molecule may be chiral or achiral. See if mirror image can be superimposed. = Chapter 5Chapter 5 5 Mirror Planes of Symmetry • If two groups are the same, carbon is achiral. (animation) • A molecule with an internal mirror plane cannot be chiral.* Caution! If there is no plane of symmetry, molecule may be chiral or achiral. See if mirror image can be superimposed. =>