What is the formal charge on the central carbon atom in allene?
The formal charge on the central carbon atom is (4 electrons – 4 bonds – 0 nonbonded = 0 E. Is the allene molecule polar? Explain. Polarity is limited by symmetry considerations; only Cn, Cnv, and Cs molecules can be polar and allene is D2d. Allene has elements of symmetry which are perpendicular. Another way to see it is that the “polarity” (dipole moment) vectors cancel out. The resultant polarity vector is 0.
