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 internal mirror plane superimposed.= of symmetry (o) Copyngh200 Pearson Prentice Hall,Ine Chapter 5 Chapter 5 7 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. =>