Chem1C_FinalHan08_FormB - Chem 1C Final June 12 2008 FORM...

Chem. 1C Final FORM
B
First letter of your last name:
June, 12, 2008
Name:
Last Name First Name
Perm #
INSTRUCTIONS: No hats allowed. No sharing of calculators. Cell Phones, iPods, headsets, etc.
must be turned off and put away.
SCANTRON FORM: Use a PENCIL
1) Write your name
2) Bubble in FORM B
3) Bubble in your PERM number (7 digits only, no extra numbers)
There are 8 pages including 1 page of info sheet and 33 questions. All questions are worth 5 points. One
question is not a multiple choice. For this, SHOW ALL YOUR WORK on the exam.
Turn in the Scantron form and your Exam upon I.D. check.
1. Each atom in HF has a fractional charge of 0.416. What is the dipole moment of HF? (Info: the distance
between H and F atoms is 9.17 · 10 -11 m and the charge of one electron is 1.60 · 10 -19 C)
(a) 1.83 D (b) 2.53 D (c) 6.10 D (d) 1.47 D (e) 4.40 D
2. Which of the following molecules has a dipole moment?
(a) PH
3
(b) SO
3
(c) BF
3
(d) NO
3
-
(e) CO
2
3. Of the ions below, which ion has the smallest atomic radius?
4. Use the bond energy values listed in the table on the next page to estimate ΔH for the combustion reaction of
ethanol. (Hint: combustion is when ethanol reacts with oxygen under high temperature. Consider the bonds that
are formed and bonds that are broken to solve this question. Also, keep in mind that the average bond energy for
the C=O bond in carbon dioxide is 799 kJ/mol as indicated on the table with *.)

5. Which of the following descriptions is incorrect?