Download CHM 2210 Test 1 September 11, 2003 Name

CHM 2210 Test 1 September 11, 2003
Name _______________________
1. Give the ground-state electron configuration for carbon (atomic number 6).
2. How many electrons does oxygen have in its valence shell?
3. Write a valid Lewis (electron-dot) structure for each formula. Show all electrons as dots and show all
non-bonding electrons.
C2Cl4 tetrachloroethylene
4. Write a valid Lewis (electron-dot) structure for each formula. Show all electrons as dots and show all
non-bonding electrons.
CH4O methanol
5. The structure of urea is shown below. Fill in any non-bonding valence electrons that are missing from the
line-bond structure.
6. The structure of urea is shown below. The carbon atom in urea is:
a.
b.
c.
d.
sp3 hybridized
sp2 hybridized
sp hybridized
not hybridized
7. The structure of urea is shown below. The predicted N-C=O bond angle in urea is:
a.
b.
c.
d.
109.5
120
180
not predictable
8. The molecular formula C2H4O can be converted into three-line bond (Kekulé) structures that are consistent with
valence rules. Which one of the following Kekulé structures is not consistent with valence rules? Explain why
the structure you chose is not consistent with valence rules.
9. Draw an orbital picture for ethylene, C2H4. Clearly label each bond type and indicate the type of orbitals involved
in each bond.
10. Propose a structure for a molecule that meets the following description. Contains one sp3 hybridized carbon and
two sp2 hybridized carbons.
11. Convert the following structure into a skeletal drawing.
Structural
Consider the structural representation below to answer the following questions.
12. Refer to Structural. This skeletal structure corresponds to the molecular formula:
a.
b.
c.
d.
C5H6O6
C7H10O6
C6H6O6
C6H8O6
Phenylalanine
Phenylalanine is an amino acid that is essential to human nutrition. The representation below shows the structure
of phenylalanine at physiological pH. Consider this structure to answer the following questions.
13. Refer to Phenylalanine. Assign any formal charges to atoms in this representation of phenylalanine.
14. Draw a tetrahedral representation of CH3Cl showing the geometry .
Use the standard wedge-dash convention.
15. Use the
convention and the crossed arrow (
indicated bond in the following compound.
) to show the direction of the expected polarity of the
The CF bond in fluorobenzene,
16. Label the acid and base in each reaction.
17. Label the acid and base in each reaction.
Equation 2-1
Refer to the following equation to answer the questions below.
18. Refer to Equation 2-1. Will this reaction take place as written? Explain.
19. An acid with a low pKa:
a.
b.
c.
d.
is a weak acid
is a strong acid
has a weak conjugate base
both b and c
20. Draw two additional resonance structures for the species below.
21. Draw two additional resonance structures for the species below.
Acidity Constants
Consider the acidity constants below to answer the following questions.
22. Refer to Acidity Constants. Which acid has the strongest conjugate base?
23. Explain why phenol has a much lower pKa than ethanol.
Reaction 2-2
Consider the acid-base reaction below to answer the following questions.
24. Refer to Reaction 2-2. Using the curved arrow formalism, show the flow of electrons for this reaction.
25. Refer to Reaction 2-2. Write the products of this acid - base reaction.