-Ñ=Ñ- -Ñ-N- Н Н Hydrazobenzene Azobenzene

Azo dyes are organic dyes that are used for many applications,
such as the coloring of fabrics. Many azo dyes are
derivatives of the organic substance azobenzene, C₁₂H₁₀N₂.
A closely related substance is hydrazobenzene, C₁₂H₁₂N₂.
The Lewis structures of these two substances are given

(Recall the shorthand notation used for benzene.)
(a) What is the hybridization at the N atom in each of the
substances? (b) How many unhybridized atomic orbitals
are there on the N and the C atoms in each of the substances?
(c) Predict the N—N—C angles in each of the
substances. (d) Azobenzene is said to have greater delocalization
of its π electrons than hydrazobenzene. Discuss
this statement in light of your answers to (a) and (b). (e) All
the atoms of azobenzene lie in one plane, whereas those
of hydrazobenzene do not. Is this observation consistent
with the statement in part (d)? (f) Azobenzene is an intense
red-orange color, whereas hydrazobenzene is nearly colorless.
Which molecule would be a better one to use in a
solar energy conversion device? (See the “Chemistry Put to
Work” box for more information about solar cells.)