Portage Learning CH219: Organic Chemistry Exam
7Questions and Verified Answers, 100% Guaranteed Pass
||Complete A+ Guide
1. Heterocycles (heterocyclic compounds)ANS: cyclic organic molecules in which
one or more carbon atoms are replaced by heteroatoms (elements other than carbon
or hydrogen)
2. What are the most common heteroatoms? ANS: oxygen, nitrogen, and sulfur
3. How many heteroatoms can be present on a heterocyclic compound? ANS:
More than one heteroatom can be present, and the heteroatoms can be the same
or different
4. True or False: Heterocyclic compounds may contain multiple bonds and the
rings may have chains or branched chains of carbons attached to them. The
rings may be of a variety of sizes ANS.: True
5. True or False: Heterocycles form the largest class of organic compounds
known. ANS: True
6. True or False: Many natural products and important drug molecules contain
heterocyclic rings. ANS: True
7. What are the two main subgroups of heterocyclic compounds? ANS:
Aromatic and aliphatic (non-aromatic)
Example of non-aromatic heterocycles include molecules like cyclic ethers (epox-
, ides) and sugars like glucose (a cyclic hemiacetal)
Non-aromatic heterocycles behave very similarly to their acyclic counterparts.
8. Pyridine ANS: A six-membered heterocyclic analog of benzene. dine, one CH
In pyri unit of the (benzene) ring is replaced by a N atom.
9. What are the bond angles between the atoms of pyridine? ANS:
Approximately 120 degrees
10. True or False: Like benzene, pyridine is a flat molecule with near-perfect
hexagonal geometry? ANS: True
11. What hybridization are the atoms of the pyridine ring? ANS: sp2
12. What makes the pyridine ring aromatic just like benzene? ANS: each atom
is sp2 hybridized and each contributes a single electron to the conjugated p
system for a total of six p electrons, making the ring aromatic just like benzene
air of
13. True or False: The nitrogen atom of pyridine contains a lone p ame plane
electrons in an sp2 hybrid orbital that is NOT orientated in the sch carbon
of the atoms in the ring (like the hydrogens that project from eathe ring.
atom). ANS: False - they are orientated in the same plane of the
atoms in
14. What are the C-C bond lengths in a pyridine molecule? ANS: 139 pm are
inter- mediate between normal C-to-C sigma and pi bonds.
7Questions and Verified Answers, 100% Guaranteed Pass
||Complete A+ Guide
1. Heterocycles (heterocyclic compounds)ANS: cyclic organic molecules in which
one or more carbon atoms are replaced by heteroatoms (elements other than carbon
or hydrogen)
2. What are the most common heteroatoms? ANS: oxygen, nitrogen, and sulfur
3. How many heteroatoms can be present on a heterocyclic compound? ANS:
More than one heteroatom can be present, and the heteroatoms can be the same
or different
4. True or False: Heterocyclic compounds may contain multiple bonds and the
rings may have chains or branched chains of carbons attached to them. The
rings may be of a variety of sizes ANS.: True
5. True or False: Heterocycles form the largest class of organic compounds
known. ANS: True
6. True or False: Many natural products and important drug molecules contain
heterocyclic rings. ANS: True
7. What are the two main subgroups of heterocyclic compounds? ANS:
Aromatic and aliphatic (non-aromatic)
Example of non-aromatic heterocycles include molecules like cyclic ethers (epox-
, ides) and sugars like glucose (a cyclic hemiacetal)
Non-aromatic heterocycles behave very similarly to their acyclic counterparts.
8. Pyridine ANS: A six-membered heterocyclic analog of benzene. dine, one CH
In pyri unit of the (benzene) ring is replaced by a N atom.
9. What are the bond angles between the atoms of pyridine? ANS:
Approximately 120 degrees
10. True or False: Like benzene, pyridine is a flat molecule with near-perfect
hexagonal geometry? ANS: True
11. What hybridization are the atoms of the pyridine ring? ANS: sp2
12. What makes the pyridine ring aromatic just like benzene? ANS: each atom
is sp2 hybridized and each contributes a single electron to the conjugated p
system for a total of six p electrons, making the ring aromatic just like benzene
air of
13. True or False: The nitrogen atom of pyridine contains a lone p ame plane
electrons in an sp2 hybrid orbital that is NOT orientated in the sch carbon
of the atoms in the ring (like the hydrogens that project from eathe ring.
atom). ANS: False - they are orientated in the same plane of the
atoms in
14. What are the C-C bond lengths in a pyridine molecule? ANS: 139 pm are
inter- mediate between normal C-to-C sigma and pi bonds.
