Ch 222 Winter 2011 - First Midterm Exam

CH 222 WINTER 2011 - FIRST MIDTERM EXAM

Form No.3

This exam has 22 questions worth 5 pts each, plus one question worth 2 pts.

The total possible scoreis 112 pts.

DO NOT OPEN THIS EXAM UNTIL TOLD TO DO SO

Before the exam begins you can do the following on the Scantron answer sheet. Use a #2 pencil.

1. Fill in your name (LAST NAME, FIRST NAME) in the large box on the left. Don't forget to bubble in the circles below your name.

2. Fill in your student ID number in the box labeled "IDENTIFICATION NUMBER". Do not use dashes or blank spaces. Fill in the circles as well.

3. In the box labeled "CLASS SECTION NUMBER", enter the appropriate number

8 am class = section 001 (Nafshun) 9 am class = section 002 (Nafshun)

11am class = section 003 (Watson)12pm class = section 050 (Muir)

4. In the lower right corner, in the box labeled "FORM NUMBER", write in the exam form number (1, 2, 3, 4 etc.) given above in the shaded box and fill in the bubble.

ONLY ONE APPROVED NOTECARD IS ALLOWED

ALL PHONES AND OTHER ELECTRONIC DEVICES OTHER THAN CALCULATORS MUST BE OFF

You may keep this exam packet and your notecard when the exam period is complete.

Hand in the Scantron answer sheet to a TA at the end of the exam.

Periodic Table

Geometry Handout

1.Place the following in order of decreasing dipole moment.

I. cis-CHCl=CHClII. trans-CHCl=CHCIIII. cis-CHF=CHF

(A)III > I > II

(B)II > I > III

(C)I > III > II

(D)II > III > I

(E)I = III > II

2.Describe a pi bond.

(A)side by side overlap of p orbitals

(B)end to end overlap of p orbitals

(C)s orbital overlapping with the end of a p orbital

(D)overlap of two s orbitals

(E)p orbital overlapping with a d orbital

3.List the number of sigma bonds and pi bonds in a triple bond.

(A)1 sigma, 1 pi

(B)2 sigma, 1 pi

(D)1 sigma, 2 pi

(E)0 sigma, 3 pi

4.Consider the molecule below. Determine the molecular geometry at each of the 2 labeled carbons.

(A)C1 = tetrahedral, C2 = linear

(B)C1 = trigonal planar, C2= bent

(C)C1 = bent, C2 = trigonal planar

(D)C1 = trigonal planar, C2 = tetrahedral

(E)C1 = trigonal pyramidal, C2 = see-saw

5.Which of the following statements is TRUE?

(A)The total number of molecular orbitals formed doesn't always equal the number of atomic

orbitals in the set.

(B)A bond order of 0 represents a stable chemical bond.

(C)When two atomic orbitals come together to form two molecular orbitals, one

molecular orbital will be lower in energy than the two separate atomic orbitals and

one molecular orbital will be higher in energy than the separate atomic orbitals.

(D)Electrons placed in antibondingorbitals stabilize the ion/molecule.

(E)All of the above are true.

6.The O-C-O bond angle in the carbonate ion, CO32-, is:

(A)90

(B)120

(D)A little greater than 109.5

(E)A little less than 109.5

7.The H-O-H bond angle in water, H2O, is:

(A)180

(B)120

(D)A little greater than 109.5

(E)A little less than 109.5

8.The molecular geometry of CF4 is:

(A)bent

(B)trigonal planar

(C)trigonal pyramidal

(D)tetrahedral

(E)octahedral

9.Consider CH4, CF4, CCl4, and NH3. Which of the following statements is correct?

(A)None of these molecules is polar

(B)One of these molecules is polar

(C)Two of these molecules are polar

(D)Three of these molecules are polar

(E)All four of these molecules are polar

10.Consider the molecule below and identify the correct statement.

(A)There are two carbons that have sp2 hybridization schemes

(B)There are three carbons that have sp2 hybridization schemes

(C)There are four carbons that have sp2 hybridization schemes

(D)There are five carbons that have sp2 hybridization schemes

(E)There are six carbons that have sp2 hybridization schemes

11.Consider MO (Molecular Orbital Theory). The F2 molecule is:

(A)diamagnetic

(B)paramagnetic

(C)metamagnetic

(D)Beyoncé-magnetic

(E)Sixx-magnetic

12.Molecular orbital theory predicts the O2- ion (a minus one charge) has a bond order of:

(A)1.0

(B)1.5

(D)2.5

(E)3.0

13.Consider MO (Molecular Orbital Theory). The N2+ (a positive one charge) ion is:

(A)paramagnetic

(B)diamagnetic

(C)tetramagnetic

(D)pentamagnetic

(E)polarmagnetic

14.Write the nuclear equation for the alpha decay of .

(A)+ →

(B)→ +

(C)→ +

(D)+ →

(E)→ +

15.Determine the identity of the daughter nuclide from the beta decay of .

(A)

(B)

(C)

(D)

(E)

16.The following reaction represents what nuclear process?

+ → +

(A)nuclear fusion

(B)alpha emission

(C)beta emission

(D)nuclear fission

(E)neutron capture

17.Determine the binding energy of an O-16 nucleus. The O-16 nucleus has a mass of 15.9905 amu. A proton has a mass of 1.00728 amu, a neutron has a mass of 1.008665 amu, and 1 amu is equivalent to 931 MeV of energy.

(A)8.84 MeV

(B)128 MeV

(D)78.1 MeV

(E)38.2 MeV

18.When an alpha particle is emitted,

(A)1 proton is converted into 1 neutron

(B)2 protons and 2 neutrons are ejected from the parent nuclide

(D)1 electron and 1 proton are combined to form 1 neutron

(E)2 positrons and 2 neutrons are ejected from the parent nuclide

19.Consider the valley of stability. What decay is expected for a species located in the extreme top right of the belt?

(A)Alpha decay

(B)Beta decay

(C)Gamma decay

(D)Electron decay

(E)Tooth decay

20.A radioactive decay series that begins with 238U ends with formation of the stable nuclide 206Pb. How many alpha particle emissions and how many beta particle emissions are involved in the sequence of radioactive decays?

(A)6 alpha and 8 beta decays

(B)6 alpha and 6 beta decays

(D)8 alpha and 6 beta decays

(E)8 alpha and 2 beta decays

21.A student obtains a sample of 59Fe (t1/2 = 44.5 days) containing 0.505 g. How many grams of 59Fe will remain after 365 days?

(A)583 g

(B)6.37 g

(D)0.00172 g

(E)0.00154 g

22.Which of the following correctly depicts the curve of nuclear binding energy?

23.So, Exam 1 is over. And now…

(A)I’m goin’ Party like it’s 1999.

(B)Vegas.

(C)Downtown with friends.

(D)Refurnish my room to resemble Gilbert 224. I plan on reliving general chemistry every day of my life; for it has been a breathtaking experience I cannot live without.

(E)I need to write a letter to decline the Nobel Prize Committee's offer because the cash prize will place me in a higher tax bracket.

[Any response will receive full credit; even no response.]