Ch. 16 Flashcards
What are annulenes?
Hydrocarbons with alternating single and double bonds
What makes an aromatic compound?
Cyclic with conjugated Pi bonds
Each atom must be sp2 or sp
Overlap continuously
What makes an un aromatic compound?
No continuous ring of overlapping p orbitals
What makes an anti aromatic compound?
The delocalization of the Pi electrons over the ring increases the electronic energy
According to Huckel’s Rule, what makes an aromatic system?
if the number of pi electrons in the cyclic system is 4n+2 the system is aromatic
According to Huckel’s Rule, what makes an anti-aromatic system?
if the number of pi electrons in the cyclic system is 4n
Common aromatic systems have ____ pi electrons
2,6, 10 pi electrons
for N=0,1,or 2
Common anti-aromatic systems have ____ pi electrons
4, 8, or 12 pi electrons
for N=1,2, or 3
in determining aromaticity, if sp3 atom is present means…
non aromatic
in determining aromaticity, if sp2 atom is present means…
aromatic or anti-aromatic
what is an heterocyclic molecule?
a cyclic structure with an atom other than carbon
What is an Allotrope?
different forms of an element with different properties
What are the allotropes of carbon?
Amorphous Carbon
Diamond
Graphite
Describe the Amorphous Carbon
small particles of graphite; charcoal, soot, coal, carbon black.
Describe Diamond
a lattice of tetrahedral carbon atoms
