CHE 105 FA17 Exam 3

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Question #: 1

Octane undergoes combustion to produce heat. This reaction is 1 [endothermic, exothermic]. The sign for ΔH for this process is 2 [positive, negative]

1.

2.

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Question #: 2

The 1 of conservation of 2 states that the energy is neither created nor destroyed.

1.

2.

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Question #: 3

Match the frequencies of light below with the corresponding portion the electromagnetic spectrum by filling in each blank with orange, microwave, ultraviolet, or green. Scroll down to see all four frequencies.

5.7×1014 s–1 1 4.9×1014 s–1 2 3.2×1015 s–1 3 6.1×109 s–1 4 1.

2.

3.

4.

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Question #: 4

An argon laser emits radiation at a wavelength of 190 nm. Calculate the energy of a mole of photons at this wavelength in units of kJ/mole.

A. 1.3×10-31

B. 7.9×10-8

C. 6.3×10-4

D. 6.3×102

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Question #: 5

How many photons are produced by a laser pulse of 449 mJ at a wavelength of 441 nm? Report your answer with three significant figures. Do NOT include units in your answer. For answers in scientific notation, use the format 2.22E2 for 2.22×102 or 2.22E-2 for 2.22×10–2 1 photons

1.

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Question #: 6

A metal surface absorbs a photon with a wavelength of 500. nm and ejects an electron with a kinetic energy of 3.40 x10-20 J. Determine its binding energy in joules.

A. 3.64 x 10-19 J

B. 3.64 x 10-20 J

C. 5.76 x 10-20 J

D. 5.76 x 10-19 J

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Question #: 7

What is the velocity (speed) of a neutron (mass=1.67 ×10-24 g) whose wavelength is 0.155 nm? 1 m/s Report your answer to three significant figures. Do NOT include units in your answer. Use the format 2.22E2 for 2.22×102 or 2.22E-2 for 2.22×10–2.

1.

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Question #: 8

The principal quantum number is given the symbol 1 , which indicates the distance from the nucleus and the energy of the orbital. The angular momentum quantum is given the symbol l and determines the 2 [energy, shape, orientation] of the orbital. When n=3, the angular momentum quantum number has a minimum value of 3 and a maximum value of 4 .

1.

2.

3.

4.

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Question #: 9

Calculate the energy of absorbed photons when an electron in a hydrogen atom undergoes a transition from n = 1 to n = 4. Report your answer with three significant digits. Do NOT include units in your answer. For numbers in scientific notation, use the format 2.22E2 for 2.22 × 102 or 2.22E-2 for 2.22 × 10–2 1 J

1.

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Question #: 10

Which one is not a possible atomic orbital?

A. 1s

B. 2p

C. 3f

D. 4d

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Question #: 11

Give the numerical value of l for the orbitals seen below. Scroll down to see all four images. Report each answer as a whole number.

l = 1

l= 2

l= 3

l = 4

1.

2.

3.

4.

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Question #: 12

According to _____, no two electrons in the same atom can have the same four quantum numbers.

A. the Aufbau principle

B. the Pauli exclusion principle

C. Hund's rule

D. the Bohr model

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Question #: 13

Identify the element represented by each electron configuration. Report each answer as a chemical symbol. 1 [Ar]4s23d104p1 2 1s22s22p5 3 [Kr]5s24d1

1.

2.

3.

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Question #: 14

Which element has atoms with exactly four valence electrons in its ground state?

A. Ca

B. Cr

C. Si

D. S

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Question #: 15

Which two elements are paramagnetic?

A. nitrogen

B. lead

C. calcium

D. krypton

E. zinc

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Question #: 16

What are the four quantum numbers for the last electron added to the electron configuration of lithium? Report your answer with numbers separated by commas (1,1,1,1). 1

1.

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Question #: 17

Which one lists the elements from smallest to largest atomic (covalent) radii?

A. Cs <Rb< He <Na <Li

B. He <Cs <Rb <Na <Li

C. Cs <He <Li <Na <Rb

D. He <Li <Na <Rb <Cs

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Question #: 18

Arrange the following ions in order of decreasing (largest to smallest) ionic radius. K+, Ca2+, S2–, Cl–. Report your answers as element symbols. 1 > 2 > 3 > 4

1.

2.

3.

4.

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Question #: 19

Which equation represents the process related to the first ionization energy of the element?

A. Cl(g) + e– →Cl– (g) + energy

B. Ca+(g) + energy →Ca2+(g) + e–

C. Ne(g) + energy →Ne+(g) + e–

D. CaCl2(s) + energy →Ca2+(g) + 2 Cl– (g)

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Question #: 20

The second period element, 1 , would experience a large increase between the third and fourth ionization energies.

1.

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Question #: 21

Electron affinity of an atom is the energy associated with the equation:

A. X—(g) →X(g) + e—

B. X(g) + e— →X—(g)

C. X(g) →X+(g) + e—

D. X+(g) + e— →X(g)

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Question #: 22

How many unpaired electrons are in a gaseous Co3+ ion in its ground state?

A. 0

B. 2

C. 4

D. 6

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Question #: 23

Which bond is most polar?

A. S-O

B. C-F

C. C-H

D. Cl-Cl

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Question #: 24

A Lewis structure of the carbonate ion (CO32-) includes 1 single bonds, 2 double

bonds, 3 triple bonds. The molecule contains 4 lone pairs of valence electrons. Report each answer as a whole number. Do NOT include units in your answer.

1.

2.

3.

4.

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Question #: 25

Which two Lewis structures are examples of exceptions to the octet rule?

A.

B.

C.

D.

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Question #: 26

The cyanate ion contains one atom each of carbon, nitrogen and oxygen and has a charge of –1. The best Lewis structure, based on formal charges, contains one single bond and one triple bond. Report each answer as a chemical symbol. The central atom is 1 [C, N, O]. The central atom forms a single bond with 2 [C, N, O] and a triple bond with 3 [C, N, O].

1.

2.

3.

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Question #: 27

Which two compounds have the larger lattice energy listed first?

A. MgO, CaS

B. NaCl, MgCl2

C. CaCl2, CaI2

D. CsI, RbI

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Question #: 28

Which substance has an electron group geometry of trigonal bipyramidal?

A. SF4

B. XeF4

C. CH4

D. XeOF4

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Question #: 29

Draw the Lewis structure of SO2. What is the electron group geometry and the molecular geometry? electron geometry 1 molecular geometry 2

1.

2.

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Question #: 30

Which compound has a non-zero dipole moment?

A. CO2

B. NH3

C. PF5

D. CCl4

DRAFTDo Not Use Until Posted.

CHE 105 FA17 Exam 3 - Confidential

Your Name: Your ID:

attachment_for_pubExamUID_lnxp115101112127312579XX_228.jpg

Question #: 1

Octane undergoes combustion to produce heat.

This reaction is     1     [endothermic, exothermic].

The sign for ΔH for this process is     2     [positive, negative]

 

1. exothermic

2. negative

Question #: 2

The     1     of conservation of     2     states that the energy is neither created nor destroyed.

1. law

2. energy

Question #: 3

Match the  frequencies of light below with the corresponding portion the electromagnetic

spectrum by filling in each blank with orange, microwave, ultraviolet, or green. Scroll

down to see all four frequencies.

 

5.7×1014 s–1     1    

4.9×1014 s–1     2    

3.2×1015 s–1     3    

6.1×109 s–1     4    

 

1. green

2. orange

3. ultraviolet

4. microwave

Question #: 4

An argon laser emits radiation at a wavelength of 190 nm.  Calculate the energy of a mole of

photons at this wavelength in units of kJ/mole.

A. 1.3×10-31

B. 7.9×10-8

C. 6.3×10-4

✓D. 6.3×102

Question #: 5

How many photons are produced by a laser pulse of 449 mJ at a wavelength of 441 nm?

Report your answer with three significant figures. Do NOT include units in your answer. For

answers in scientific notation, use the format 2.22E2 for 2.22×102 or 2.22E-2 for 2.22×10–2 

    1     photons

1. 9.96e17|9.96E+17|

Question #: 6

A metal surface absorbs a photon with a wavelength of 500. nm and ejects an electron with a kineticenergy of 3.40 x10-20 J. Determine its binding energy in joules.

✓A. 3.64 x 10-19 J B. 3.64 x 10-20 J C. 5.76 x 10-20 J D. 5.76 x 10-19 J

Question #: 7

What is the velocity(speed) of a neutron (mass=1.67 ×10-24 g) whose wavelength is 0.155 nm?

    1     m/s

Report your answer to three significant figures. Do NOT include units in your answer.  Use the

format 2.22E2 for 2.22×102 or 2.22E-2 for 2.22×10–2. 

1. 2.56E3

Question #: 8

The principal quantum number is given the symbol     1    , which indicates the distance from the

nucleus and the energy of the orbital.  The angular momentum quantum is given the symbol l

 and determines the     2     [energy, shape, orientation] of the orbital.  When n=3, the angular

momentum quantum number has a minimum value of     3     and a maximum value of     4    .

1. n

2. shape

3. zero|0|

4. two|2|

Question #: 9

Calculate the energy of absorbed photons when an electron in a hydrogen atom undergoes a

transition from n = 1 to n = 4.

Report your answer with three significant digits. Do NOT include units in your answer. For

numbers in scientific notation, use the format 2.22E2 for 2.22 × 102 or 2.22E-2 for 2.22 × 10–2

    1     J

1. 2.04E-18|+2.04E-18|

Question #: 10

Which one is not a possible atomic orbital?

A. 1s B. 2p

✓C. 3f D. 4d

Question #: 11

Give the numerical value of l for the orbitals seen below. Scroll down to see all four images.

Report each answer as a whole number.

l =     1     l=    2    

 

1. 2

2. 0

3. 3

4. 1

Question #: 12

According to _____,  no two electrons in the same atom can have the same four quantum

numbers. 

A. the Aufbau principle

✓B. the Pauli exclusion principle C. Hund's rule D. the Bohr model

Question #: 13

Identify the element represented by each electron configuration. Report each answer as a

chemical symbol.

    1     [Ar]4s23d104p1

    2     1s22s22p5

    3     [Kr]5s24d1

1. Ga

l=     3    l =    4    

2. F

3. Y

Question #: 14

Which element has atoms with exactly four valence electrons in its ground state?

A. Ca B. Cr

✓C. Si D. S

Question #: 15

Which two elements are paramagnetic?

✓A. nitrogen ✓B. lead

C. calcium D. krypton E. zinc

Question #: 16

What are the four quantum numbers for the last electron added to the electron configuration of

lithium?  

Report your answer with numbers separated by commas (1,1,1,1).

    1    

1. 2,0,0,+1/2|2,0,0,-1/2|

Question #: 17

Which one lists the elements from smallest to largest atomic (covalent) radii?

A. Cs <Rb< He <Na <Li B. He <Cs <Rb <Na <Li C. Cs <He <Li <Na <Rb

✓D. He <Li <Na <Rb <Cs

Question #: 18

Arrange the following ions in order of decreasing (largest to smallest) ionic radius.  K+, Ca2+,

S2–, Cl–.

Report your answers as element symbols.

    1     >    2     >    3     >    4    

1. S

2. Cl

3. K

4. Ca

Question #: 19

Which equation represents the process related to the first ionization energy of the element?

A. Cl(g) + e–   →Cl– (g) + energy B. Ca+(g) + energy →Ca2+(g) +  e–

✓C. Ne(g) + energy →Ne+(g)  + e–

D. CaCl2(s) + energy →Ca2+(g)  + 2 Cl– (g)

Question #: 20

The second period element,      1    , would experience a large increase between the third

and fourth ionization energies.

1. boron|Boron|B|

Question #: 21

Electron affinity of an atom is the energy associated with the equation:

A. X—(g) →X(g) + e—

✓B. X(g) + e— →X—(g)

C. X(g) →X+(g) + e—

D. X+(g) + e— →X(g)

Question #: 22

How many unpaired electrons are in a gaseous Co3+ ion in its ground state?

A. 0 B. 2

✓C. 4 D. 6

Question #: 23

Which bond is most polar?

A. S-O

✓B. C-F C. C-H D. Cl-Cl

Question #: 24

A Lewis structure of the carbonate ion (CO32-) includes     1     single bonds,     2     double bonds,

    3     triple bonds. The molecule contains     4     lone pairs of valence electrons.

Report each answer as a whole number. Do NOT include units in your answer.

1. 2|two|

2. 1|one|

3. 0|zero|

4. 8|eight|

Question #: 25

Which two Lewis structures are examples of exceptions to the octet rule? 

✓A.

B.

✓C.

D.

Question #: 26

The cyanate ion contains one atom each of carbon, nitrogen and oxygen and has a charge of –1.

The best Lewis structure, based on formal charges, contains one single bond and one triple bond.

Report each answer as a chemical symbol.

The central atom is     1     [C, N, O].

The central atom forms a single bond with     2     [C, N, O] and a triple bond with     3     [C, N, O].

1. C

2. O

3. N

Question #: 27

Which two compounds have the larger lattice energy listed first?

✓A. MgO, CaS

B. NaCl, MgCl2 ✓C. CaCl2, CaI2

D. CsI, RbI

Question #: 28

Which substance has an electron group geometry of trigonal bipyramidal?

✓A. SF4

B. XeF4 C. CH4 D. XeOF4

Question #: 29

Draw the Lewis structure of SO2.  What is the electron group geometry and the molecular

geometry?

electron geometry     1    

molecular geometry     2    

1. trigonal planar

2. bent

Question #: 30

Which compound has a non-zero dipole moment?

A. CO2

✓B. NH3 C. PF5 D. CCl4