10:20 Exam II Key; FALL 2017 Dr. Williamson (The key was changed about 11:30 on 10/23 for P#9, B #13, and Y #11)

Pink, Exam II, v1 Blue, Exam II, v2 QUESTION Yellow, Exam II, v3
5.5 pts each unless noted  5.5 pts each unless noted   5.5 pts each unless noted
B (A=2.5 pts) E 1 C
C A 2 E (A=2.5 pts)
C E 3 D (E=2.5 pts)
A B 4 E or C
A (D=2.5 pts) D 5 D
A C or E 6 B
B A 7 E (B=3.5 pts)
C or E E (A=2.5 pts) 8 B
C, B D (B=3.5 pts) 9 E
A B 10 D
A (C=3.5 pts) A 11 C, A
A A (B=2.5 pts) 12 D
D E, B 13 D
B D 14 B

(14 MC x 5.5 pts each) = 77 pts + short answer 23 pts = 100 pts on the total exam
To find your grade: (the number of MC questions you got totally correct x 5.5) + any partial points = the total multiple choice out of 77. Later you will add to this your short answer grade (deducting 1 pt if you did NOT bubble your name and UIN correctly)

See the total key posted in the glass case outside room 123 HELD. For short answer, if you gave both the electronic and molecular geometry, then 1pt for shape. The shape, hybridization, and polarity must match your drawing for credit on those three.

  Species val. e-
1pt
drawing
3pt
brackets & ion charge 1pt

shape of molecule
2pt

hybrid.
2pt
Polar or nonpolar
2pt

Dissolve
2pt

Pink OBr2 20 2 single bonds and 2 lone electron pair on central atom --- bent sp3 polar water
Pink ICl4- 36 4 single b. and 2 lone e- pair on central atom with a neg. charge yes square planar sp3d2 nonpolar --
Blue XeF2 22 2 single bonds and 3 lone e- pair on central atom --- linear sp3d nonpolar CCl4
Blue NH2 - 8 2 single bond and 2 lone e- pair on central atom with a neg. charge. yes bent or angular sp3 polar --
Yellow IF3 28 3 single bond and 2 lone e- pair on central atom --- T-shaped sp3d polar water
Yellow CO2-2 18 1 single b, 1 double b. and 1 lone e- pair on central atom with a neg. charge yes bent sp2 polar --